Echo correlation analysis and acoustic evidence in the Kennedy assassination [Free Republic]

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A Dallas Police Department recording contemporaneous with the Kennedy assassination contains five impulsive sounds that have the acoustic waveform of Dealey Plaza gunfire. One of the sounds matches the echo pattern of a test shot fired from the Grassy Knoll. The shock wave precedence associated with this pattern is consistent with the muzzle velocity of a .30 calibre rifle. Criticism of the acoustic identifications on statistical grounds is based on erroneous assumptions concerning the assignment of values to the parameters that determine the probability that random noises could resemble gunshot patterns. A conservative estimate of the true value of the probability that the putative Grassy Knoll shot is attributable to random radio noise is no greater than 0.037. Alleged asynchroneity of the sounds with the time of the assassination stemmed from several incorrect assumptions. Whatever their origin, the gunshot-like sounds occur exactly synchronous with the time of the shooting.

The validity of acoustic evidence for a gunshot from the ‘Grassy Knoll’ was challenged on statistical grounds and on the basis of an anomaly on the Dallas police recordings. However, the assumptions underlying those criticisms were not in accord with evidence overlooked by the review panel. With a rigorous statistical analysis one arrives at a calculation for the probability that the recording contains a random pattern which by chance resembled the acoustic signature of a gunshot from the Grassy Knoll at no more than p = 0.037.

The NRC panel asserted that radio cross-talk indicated asynchroneity between the putative gunshots on channel one and the time of the assassination revealed by context on channel two. The NRC panel overlooked that an alternative synchronization arises from the radio cross-talk evidence because of the fact that the two identifiable cases of cross-talk were out of synch with one another. The episodes are three minutes apart on one channel, but only two minutes apart on the other. Had the unambiguous instance of cross-talk been used, instead of the barely audible fragment of cross-talk, the supposed asynchroneity in the evidence would have been resolved. The unambiguous cross-talk evidence indicates that the gunshot-like sounds on channel one were recorded over the police radio at the precise instant in real time that the President was being assassinated by gunfire.

The order in the data, that is, the congruence between the acoustic evidence and the sequence of events derived from a reconstruction of the crime from video evidence is the major factor that led acoustic experts to conclude that there was a gunshot from the Grassy Knoll during the assassination. The critiques of the acoustic evidence by the NRC panel and the FBI laboratory failed to consider that evidence. There was a further incongruity in the arguments of the NRC panel, and perhaps irony, in that a broadcast over the police radio sent one minute after the assassination giving orders to search behind the Grassy Knoll for an assassin, was invoked as evidence that there was no assassin on the Grassy Knoll.

This thread is for the discussion of the acoustic evidence and this and prior studies of it. It is NOT a general discussion about the JFK assassination. There is an ongoing thread for that purpose, currently here:

The following is a post from Fred25 that I copied to this thread from another thread.:

Ok, I’ve just had a chance to glance over the new acoustics report, and I see a couple of problems with it already. In the introduction it speaks of “five impulsive sounds that have the acoustic waveform of Dealey Plaza gunfire”. Well, the House Committee sound labs mentioned only four gunshots. How can there be 5 matching “waveforms” but only 4 shots?

The first visual print-out illustration of a Dealey Plaza 1978 test gunshot has an arrow pointing to the “Muzzleblast” but it has no arrow pointing to the concussion wave or “sonic boom” caused by the supersonic bullet. It’s there on the graph, but there is no arrow pointing to it and there are no such waves shown on the Dallas Police graph. I think everyone agrees that the Carcano bullets were supersonic, so where are the three “sonic boom” spikes on the DPD print-out graph?

The report states, “A check of ballistic tables from 1963 [66] shows more than a dozen commercially available cartridges with a muzzle velocity of 748 +32 m/sec, most of them in the .30 calibre range. The popular .30-30 Winchester with a muzzle velocity of 735 m/sec falls in this category and is noteworthy in the context of the Dallas Police tapes. At 12.45 pm, 15 mm after the shooting, a police officer in Dealey Plaza radioed in the following information over channel one:

‘The wanted person in this is a slender white male about thirty, five feet ten, one sixty five, carrying what looked to be a 30-30 or some type of Winchester’ [67].”

This is extremely misleading, and the author should know that. The “30-30” reference is to what Dealey Plaza witnesses thought saw in the 6th floor window. This is very clear when you listen to the entire Channel 2 recording, from 12:30 to 12:45, as Dealey Plaza cops gradually report in to the dispatcher that witnesses say they saw that the shots came from Book Depository.

No one at all, on the street level, could clearly identify the rifle from that distance in that short amount of time, so they were reporting what they “thought it looked like”, ie a “deer rifle” type of gun, rather than a pistol or a shotgun.

There are no reports on the DPD recordings of any shots coming from the knoll. After the shooting, several cops ran around asking witnesses what they saw, and those cops put together the most common and decisive consensus of opinion, which they reported to the police dispatcher. You will be able to hear this when I send you a copy of the tapes.

After you get through doing your study, I’ll send you my edited version and we can compare our timing/synchronization estimates.

In the introduction it speaks of “five impulsive sounds that have the acoustic waveform of Dealey Plaza gunfire”. Well, the House Committee sound labs mentioned only four gunshots. How can there be 5 matching “waveforms” but only 4 shots?

"With this procedure, five of the six evidence patterns were found to match to one or more of the test patterns to an arbitrarily selected level of r = 0.6 or higher. The first of the six evidence patterns did not match any test pattern and was ruled out as a gunshot [24]. Another evidence pattern, the fourth in order, passed the binary correlation test, but was ruled out as a gunshot based on non-acoustic evidence, The order and spacing of the evidence patterns and the correlation coefficients for each match to the test patterns is shown in Table 1."

So there are actually six impulses, but the first one is qaulitatively different from the others and is ruled out as static. OK, I can accept that.

That still leaves five and then they say the fourth in the sequence was ruled out on "non-acoustic" evidence, and they don't tell us what the evidence is. That indicates to me that it couldn't be ruled out just on its acoustic merits. Which would then mean that that impulse appeared in its nature to be like the other four impulses that are considered to be shots. Well if that isn't a shot, what is it? Whatever it is made a sound signature that looks like a shot, so why couldn't it have made the others?

First, the print out included with the report is of such low quality that I'm reserving any judgement on signal characteristics until I have a copy of the DPD tape. Otherwise, I can quote from this passage:

"The percussive noise that is associated with the discharge of a weapon is the muzzle blast. Observed on an oscillograph, the muzzle blast appears as a brief duration (c. 5 msec), large amplitude wave with a narrow peak. Different weapons produce discernibly different waveforms, however, the automatic gain control built into the Dallas Police radio system produced distortion in the signal such that the waveform could not be relied upon for identifying the type of weapon or even if the sound actually was a muzzle blast from a weapon [13]. Alternatively, the limiting circuitry does not affect the time history of the incoming signal."

An automatic gain control cuts off signals that are too strong. That is why the peaks in the two printouts in the report don't match scale.

Agreed. This was one of a couple of passages that I thought should have been left out of the study as pointless, and delving into non-acoustic areas. It's prettly clear what the author's bias is, but I believe the science stands or falls on its own, so I only want to deal with the acoustics.

"A conservative estimate of the true value of the probability that the putative Grassy Knoll shot is attributable to random radio noise is no greater than 0.037."

"Ok, I’ve just had a chance to glance over the new acoustics report, and I see a couple of problems with it already. In the introduction it speaks of “five impulsive sounds that have the acoustic waveform of Dealey Plaza gunfire”. Well, the House Committee sound labs mentioned only four gunshots. How can there be 5 matching “waveforms” but only 4 shots? "

People who have actually read the House Select Committee on Assassination Reports (which apparently does not include Fred) know that the committee, claiming budget concerns, restricted the then-costly acoustic analysis to only four of the impulses on the tape.

Yes? Do you know something about the statistical analysis you'd like to share? Is there a flaw in it? I admit I'm not a statistician, but it looks very thourough. I'm sure you wouldn't make dismissive comments like that simply based on the fact that the conclusion contradicts your own preconceived ideas, would you?

Do you have a link to the House Committee reports? I haven't found it online yet. I will need the acoustic studies from that to check this one.

FYI, my own "preconceived ideas" are probably identical to yours on this subject. But must we use mumbo jumbo to communicate?

LOL. Good point! My remark will haunt me after you read our ninth circuit brief, I'm sure.

One of the very substantial difficulties is that they had to deal with a very old tape made on equipment that predated 1963 (in fact, I think it was a DictaPhone recording, which would be early 1950s technology) whose acoustic "survivability" after more than 30 years was uncertain, which at best was a recording made via police radios of the type in use in the early 1960s, all extremely lo-fi, and piling one poor-quality sound system atop another. One of the most important comments relevant to that was the Warren Commission testimony of Jackie Kennedy, that she was not aware of the shots being fired because she had been in a LOT of motor processions with motorcycle escorts and the motorcycles were "always backfiring" and the backfiring sounded so much like shots.

An additional problem about placing a shooter on the so-called Grassy Knoll is that there were people there, and even behind the Grassy Knoll (a railway yard, I think), who would have noticed - and acted - if someone nearby them was shooting, only they didn't.

That still leaves five and then they say the fourth in the sequence was ruled out on "non-acoustic" evidence, and they don't tell us what the evidence is.

That means that the House Committee found no darn evidence of any kind that there were any shots from the grassy knoll. And almost no “witness” in Dealey Plaza reported 5 shots. Some reported 2, most 3, and some 4. But almost none reported 5.

The HC sound labs needed at least one shot from the knoll, so they could keep the conspiracy myth alive. The author of this new report needs one shot from the knoll also (4 shots in all), to keep the myth alive, but he doesn’t need two shots from the knoll. Yet he claims to have evidence of five shots all together, but he only needs four, so he just throws one of them out right away. That is a very UNprofessional thing for a “scientist” to do. This guy is obviously political.

If, during my investigation, I had found “acoustical evidence” of 20 shots, my Final Report would had said so.

That indicates to me that it couldn't be ruled out just on its acoustic merits.

Which would then mean that that impulse appeared in its nature to be like the other four impulses that are considered to be shots. Well if that isn't a shot, what is it?

Whatever it is, made a sound signature that looks like a shot, so why couldn't it have made the others?

Right! And the ENTIRE stuck microphone sequence is filled with these noise “spikes”. Those first sound-lab guys tried to guess where in the stuck mike sequence the shots might have been timed, and then they looked at the spikes in that sequence and tried to match them up with the 1978 spikes, only they just didn’t hear the “hold everything secure” crosstalk that was imbedded in that same sequence. Again, very UNprofessional, and quite political.

An automatic gain control cuts off signals that are too strong. That is why the peaks in the two printouts in the report don't match scale.

Well there are some other factors too. First, the HC sound lab wanted the scales to look similar, because they were presenting them to the public and to a bunch of Congressmen who knew nothing about acoustics.

Auto gain control devices in 1963 were not fast acting. They were quite slow. So slow that the initial gunshot sound could be over with and finished, before the electronics of the circuitry reacted. That would serve only to dampen the sounds of the later echoes, but not the initial sharp gunshot spike.

With all the background noise of the stuck microphone sequence, the AGC was already being activated, since the microphone seems to have been bouncing around, or at least reacting to the noise of the motorcycle. The microphone could have been rattling around on its U-shaped mike cradle or “latch”. That constant “clacking” noise would have activated the AGC constantly.

The 1978 knoll shots were fired from about 350 feet to about 150-200 feet from the recording microphones, so the shot sounds wouldn’t have been tremendously loud at the microphones, but they would have clearly been recognizable as gunshot sounds. Also, I think the sound lab used professional microphones and professional tape equipment to record the sounds, then they later did some kind of special “sound processing” to make the sounds seem like they were recorded on the 1963 Dictaphone/dictabelt system.

However, JC Bowles, who was in charge of the DPD radio room in Dallas in 1963, and worked on the 1978 acoustics test for the HC, played me a recording made in Dealey Plaza by a real police microphone and radio during the test firings. The Dallas cops actually transmitted the sounds of the test firings to their headquarters, where those sounds were recorded, and what that revealed was that every loud rifle shot could clearly be heard as a loud rifle shot on the 1978 DPD recordings. I don’t think Bowles used a Dictaphone, I think he used a tape machine to record the sounds, but his sounds were more accurate, because they were picked up in Dealey Plaza with a police microphone and radio, and transmitted to headquarters where they were recorded.

I don’t think I have a copy of the 1978 DPD tapes. Bowles played those gunshots sounds for me in his office, but I don’t remember if my own recorder was going at the time.

The sound labs had no idea which mike was stuck – I say it was one at the Trade Mart – so they had to decide which one they wanted to be stuck, so they could more closely match their specially “processed” 1978 spikes with the 1963 original stuck-mike spikes. So, they decided the stuck mike was to be on a motorcycle that was just turning onto Elm when the shots were fired. Again, very unprofessional.

I don’t see any AGC “distortion” in the “signal” at all. The print-outs show neat clean spikes, “N-waves”, just like with a single gunshot and echoes, or with the “clacking” sound made by a mike bouncing against the frame of a motorcycle.

The smaller trail-off spikes on the 1978 recording are basically echoes of the initial gunshot spike. They are of different lengths and distances from the initial spike, because they are reflections coming from various buildings and other structures in Dealey Plaza. A wide building at a greater distance from the mike, would produce a larger spike (but delayed by more time) than a spike produced by an echo from a smaller building nearer the mike. In other words, the smaller building near the mike would produce a small echo sooner, but a larger building further away from the mike would produce a large echo later. Note in figure 1, there are some small spikes just before the first big medium-sized spike.

As the 1978 gunshot spikes trail off in size and time, we begin to see echoes of echoes.

Look at the drawing of where the sound labs claimed the motorcycle was. It is shown as being right down below Oswald’s window (Position 3, Figure 3 is directly below the window), yet on the House Committee tapes, using the 1978 gunshot sounds, just about all the gunshot sounds are of an equal volume (magnitude). The first two shots are as loud as the last two shots, and the grassy knoll shot is as loud as the Depository shots. This would not have been the way a real police microphone would have picked up the shots. The shots fired closer to the microphone would have been much louder than the shot fired from further away.

Later on, I’ll send you a video of the sound lab’s edited version of the Zapruder film, which includes their 1978 gunshots, and also a 1981 or ’82 appearance of Robert Blakey showing the “sound” film on NBC's Tomorrow program.

The Channel 1 recording was made on a red dictabelt which was not a tape. A diamond needle cut a groove in a wide plastic belt to make the recording. Channel 2 was recorded on a Gray Audograph disk machine, also a needle-in-groove machine. I’ve got duplicates of both machines. The Dictaphone company sent me some old samples of the red belts, and an old lawyer gave me some of his old Gray Audograph blank disks, which were blue.

The Dictaphone was very similar to the machine used to record LBJ’s swearing in, on the airplane.

Huh? That’s ridiculous. You’re making stuff up. The “impulses” were printed out side by side on a single piece of paper. All the guys had to do was look at the paper.

By the way, in this argument, YOU are supporting the OFFICIAL GOVERNMENT House Committee Report, and I am trying to REFUTE it. So, on THIS topic, YOU are the “government shill”.

By the way, where are all the supersonic “shock waves” that should precede the muzzle blasts in the Channel 1 recording in Figure 2?

It's pretty clear what the author's bias is, but I believe the science stands or falls on its own, so I only want to deal with the acoustics.

I disagree. Right now, we are NOT analyzing the ACOUSTICS evidence. We are analyzing someone else’s REPORT on the acoustics evidence. I say we should consider everything that is said in that report. Regarding some of the more complicated mathematical baloney, we don’t know if the guy is lying or not, but we can pick up on his propensity to lie and exaggerate, by studying the parts of the report that we all can understand very well. A “scientist’s” propensity to lie MUST be considered in any and all of his reports, and in every sentence of his reports.

“The analytically determined microphone location was 1.2 m closer to the President, a distance of 43 m. The acoustically determined shooter location was 2.4 m west of the corner of the fence and thus the distance to the President was 30.5 m.”

2.4 meters west of the corner of the fence? Just about 15 feet away from the three guys who were on the steps? That’s absurd. Had it been a “30-30” rifle shot, as the author claims, those guys would have jumped at the sound of the loud noise! Have you ever been 15 feet in front of a 30-30 deer rifle going off? Those guys would have hit the deck!

I have no trouble accepting, for the sake of argument, that the oscillographs as printed in the study are what a real gunshot would look like after being filtered through the microphone, radio, AGC, recording equipment that existed. Something to keep in mind is that the volume isn't used in any of the tests. It is the pattern of the peaks that is used in the echo-location analysis.

I don't have a copy of the original recording. I do have something I believe is a copy of the 1978 test recordings. As I've said, I really can't critique the waveforms as printed in the document, they are too poor. I am going to proceed on the assumption that the patterns mean what they say they mean, until I have a copy I can really look at for myself.

Here’s Zapruder’s view of the fence. Don’t you think he and his secretary would have seen and heard a gunman firing 2.4 meters West the corner of that fence? (This view is to the West.) There was a guy on that sidewalk, and three guys on the steps just to the left of this picture.

Here’s the view our own “shooter” took from the corner of the fence. The three guys were on those steps. Don’t you think they would have heard the shot of a 30-30, from 15-20 feet away? A fence shooter would have had to have been firing right through or over their heads.

Understand propaganda..... All of these threads started with that Washington Post article. It contained no critique and no photos. It was just pro-conspiracy propaganda about this latest “acoustics” report. That’s what led the original poster to post the article and to begin arguing in favor of conspiracy, although he had no evidence, no documentation, and no photos. He doesn’t have a copy of the DPD recordings, and he’s probably never read the House Committee report or the National Academy of Sciences Report. He’s just passing along meme viruses and urban legends, from one poor sucker to another. Intelligent liberals and leftists understand how this propaganda works. They’ve been manipulating our media for decades. Some of them produce a “scientific report” that almost no one bothers to read, and few people can understand, and it gets summarized and promoted in the Washington Post, which millions of people hear about.

Of course conservatives and Republicans use propaganda too, but I think liberals, leftists, and Democrats are better at propaganda than conservatives and Republicans are.

Had it been a “30-30” rifle shot, as the author claims, those guys would have jumped at the sound of the loud noise! Have you ever been 15 feet in front of a 30-30 deer rifle going off? Those guys would have hit the deck!

How do you know what anyone did at the moment shots were fired? It's a fact that several people standing in front of the grassy knoll testified to the Warren Commission that they heard shots being fired directly behind them. The WC found some rationale to discount what they said.

Volume must be considered, if the shots are recorded on the original DPD recording, especially if the sound lab is correct that the motorcycle is directly below Oswald’s window at the time of his first or second shot. That shot would have been broadcast loud through the police radio, but the “fence” shot would have been much weaker.

I’m fairly familiar with different types of radios, microphones, and gunshot recordings. I used to be an editor for Petersen’s CB Life magazine back in the ‘70s, and I’ve recorded gunshot sounds with microphones ranging in price from $5 to $300, and from near and far, supersonic and non-supersonic.

I disagree. Right now, we are NOT analyzing the ACOUSTICS evidence. We are analyzing someone else’s REPORT on the acoustics evidence. I say we should consider everything that is said in that report.

I do understand where you are coming from, but my point of view is this. This study may be wrong, and all those criticisms you offer, not based on acoustics, may be valid. If it is wrong though, then there is a failure in the acoustical analysis somewhere. That is what I want to find. I believe that if this study is flawed it should be demonstrated on its own terms, which means on the basis of the acoustical evidence.

On the other hand, if every analysis is examined and it survives criticism, and the hard science tells us that there just had to be a shot from the knoll on that tape, then that is what we should accept too. As I mentioned in an earlier discussion with someone else, we can't select the weaker evidence over the stronger because it supports a certain conclusion. Physical evidence like echo-location trumps our opinions about what people should have heard or should have acted.

I have nothing to fear from the truth. If there was no shot from the knoll, then there is no way this study can prove there was. All the more reason to take it seriously and pick it apart.

Figure 1 and Figure 2 don’t match up. If Figure 1 is a sound-lab recording of a shot from the fence, and Figure 2 is a DPD recording of a shot from the fence, then Figure 1 should overlay Figure 2 in a perfect match, with extra or extraneous peaks appearing on Figure 2 (to account for the other noise in Dealey Plaza that day, plus the microphone being bumped), but an overlay of Figure 1 doesn’t match Figure 2. Note that there is no “shock wave” spike preceding the muzzleblast in Figure 2.

Physical evidence like echo-location trumps our opinions about what people should have heard or should have acted.

I'm going to take some of the important parts from the study and post them and comment on them so that we can further the discussion about what is in it. I'll start with a little background taken from the begining.

One of the forensic issues surrounding the Kennedy assassination is the validity of acoustic evidence for a gunshot emanating from the so-called “Grassy Knoll” [1]. The President’s Commission on the Assassination of President John F Kennedy, more widely known as the Warren Commission, concluded that no more and no less than exactly three shots were fired by a single assassin from a building (Book Depository) at the northeast corner of Dealey Plaza, a park-like area in the downtown district of Dallas, Texas [2]. The number of shots, and therefore, allegations of a wider conspiracy, has been a matter of contention. Acoustic evidence pertaining to this matter was found in recordings of Dallas Police Department radio transmissions contemporaneous with the incident.

The police were using two radio channels for communications at the time of the assassination. Routine transmissions were made over a frequency designated as channel one and were recorded on a sound-actuated Dictaphone belt recorder. An auxiliary frequency, designated channel two, was dedicated to the President’s motorcade and its transmissions were recorded on a sound-actuated Gray Audograph disc machine. Each channel had its own dispatcher and, in accordance with radio protocol, each dispatcher announced the time at regular intervals. The context of the transmissions, and the dispatcher’s time notations on channel two, established that the assassination occurred between 12.30 and 12.31 pm central standard time [3]. Simultaneously, for about five and a half minutes between 12.28 and 12.34 pm, channel one transmissions were dominated by the sound of a motorcycle with a faulty relay causing the radio microphone to switch open intermittently. About half-way through this particular motorcycle transmission there occurs a sequence of static-like noises interpreted by some listeners to be possible gunfire [4].

The Dallas police recordings were acquired by the US Congress, House of Representatives, Select Committee on Assassinations (HSCA), and subjected to a forensic analysis in 1978. An independent laboratory, Bolt, Baranek & Newman inc., of Cambridge, Massachusetts, was contracted to analyse the dictabelt and a first generation taped copy of the channel one transmissions. These acoustic analysts concluded that: the motorcycle with the open microphone was in the President’s motorcade (one of 18); that sounds as loud as gunshots are on the recording; and that these included a sound pattern that might be attributed to a gunshot originating from the Grassy Knoll [5].

Because of a degree of uncertainty attached to this detection a second laboratory was asked to review the evidence. Specialists in sonar applications with the Computer Sciences Department of the City University New York concurred that the recording did include the acoustic signature of a gunshot emanating from the Grassy Knoll. In their final reports, both laboratories estimated that the likelihood of the relevant acoustic pattern being a chance array of random radio noises was no more than 5% [6,7]. Their findings were instrumental in the HSCA’s conclusion that there probably was a conspiracy behind Kennedy’s murder [8].

In 1980, the United States Department of Justice arranged with the National Research Council (NRC) for a reanalysis of the data produced by the HSCA. The NRC panel found evidence that the alleged gunshot sounds were not synchronous with events linked to the assassination and thus concluded that the impulsive sounds on the tape could not be the assassination gunfire [9]. They adopted the alternative theory that the sounds on the tape were most likely random radio noises which by chance gave rise to impulse patterns bearing a resemblance to the echoes of gunfire. The panel specifically recalculated the probability of the sound pattern being a Grassy Knoll gunshot, as opposed to random radio noise, at only 78% [10]. In general practice, the 95% significance level is widely accepted as the standard for rejecting a null hypothesis [11,12]. In this case, the null hypothesis is that the acoustic pattern is not a gunshot from the Grassy Knoll, but random noise, if the probability of the null hypothesis is as high as p = 0.22 as calculated by the NRC, rather than p = 0.05 calculated by the HSCA’s analysts, then the null hypothesis would not be rejected.

That should help everyone get up to speed on what we are talking about. I don't think there is anything in dispute in that narrative. There is an interesting point, to me. The NRC panel that disputed the House findings of a shot from the knoll, still computed the probability that the sounds were gunshots at 78%! The statistical cutoff to accept it as proven however was 95%.

You can see the guys in a clear copy of the Nix film. One of the guys turns and starts to run up the steps, which would be heading closer to the fence. He is reacting to seeing Kennedy’s head explode and seeing Jackie crawl on the back of the limo.

They can be seen in the Mooreman photo. The three guys are a little further down the steps than I remember, but they would be about 20 or so feet away from the fence, and in this photo, you can see daylight between the fence and the tree line. I think it was the guy in the front, in the dark clothes, who turned and started to run up the steps after the head shot. He would have been running closer to the fence.

This new acoustics report says the shooter was just 2.4 meters from the corner of the fence. That’s a little more than a body length. Look, there’s no one there. The motorcycle cop in this picture is looking at Kennedy, in the general direction of the fence. He heard no 30-30 shot and he saw no gunman fire from that position. Nor did the Secret Service agents in the front seat of the limo, nor did anyone else.

No one SAW a gunman fire from that position. No one HEARD a gunman fire from that position.

...In an urban environment, such as Dealey Plaza, the muzzle blast will resonate off the prominent structures creating echoes. Thus, the pattern of a gunshot in an urban environment appears on an oscillograph as a train of impulses. The time-lag between the muzzle blast and any particular echo is a function of the difference in the distance traveled by the blast from the origin to the microphone and the alternate path distance to the echo producing structure and from there to the microphone. This parameter is the echo delay time and the specific pattern that arises is the acoustic fingerprint. The pattern resulting from each combination of shooter and microphone location is complex and unique and by applying echo location principles one can isolate the origin of the sound. The echo correlation technique has been successfully applied in other cases. For example, the origin of gunfire was determined from recordings in the case of the Kent State shooting and likewise in the Greensboro, North Carolina incident known as the “Commie-Klan shootout” [14].

This is a little explanation of echo-corelation, which is key to this study. It is not just about hearing alleged gunshot sounds on a tape, it is about placing those sounds in the 3D environment of Dealey Plaza using echo-corelation.

It mentions one can isolate the origin of a sound this way, which is true. One could also solve the the location of the microphone if the sound source is known. This study attempts to do that as well.

Yeah, we see people running toward the grassy knoll. People running toward the grassy knoll immediately after the shots were fired is well known. You're citing this as proof no shots were fired there?

I'm not sure what you mean by that position. People standing in front of the grassy knoll testified to the Warren Commission that they heard shots directly behind them. It's a matter of public record. I guess they didn't identify that precise location of the fence, if that's what you mean.

The House Committee used 4 different groups of sound lab technicians. Two groups said there were NO gunshots on the police recordings, but Democrats on the Committee weren’t satisfied with that, so they hired another sound lab to set up the test firing in Dealey Plaza in 1978. That lab said there were 4 shots on the recording, but I think they said it was only a 50-50 chance. Then they sent their work to a fourth sound lab, and they said there was a 95% chance of 4 gunshots on the recording.

But here is a National Academy of Sciences report that shows the 3rd sound lab’s position on the recording for the extra shot WAS AT A DIFFERENT PLACE than the position the 4th lab decided on.

All of this was liberal and leftist Democrat politics, back during the Carter years. The JFK “conspiracy” hoax benefits the Democrats more than the Republicans.

Some of the guys on this thread are looking for a “government conspiracy”, well, here it is. The last two House Committee sound lab reports were faked, for liberal political purposes.

By “that” position, I mean 2.4 meters west of the fence corner. We are discussing this latest “acoustics” report, and that’s where the author says the gunman was.

People did NOT run up on the grassy knoll “immediately” after the shots. The films you have seen of the people running up the knoll were taken about two minutes after the assassination. They were running up to see if they could see what happened to the limousine after it turned onto the Stemmens freeway.

I have a film of a motorcycle cop running up the steps toward the fence, and then along the fence line to the triple overpass, in response to Sheriff Decker’s order to “get someone” up on that overpass. He saw no gunman, no one behind the fence, and no one running away. The couple of dozen people on the triple overpass had a clear view of all of the fence, and they saw no gunman.

Are you aware that the people who were standing on the SOUTH grassy knoll said they thought the shots came from behind them? That’s told as eyewitness accounts in “Six Seconds in Dallas”, but their stories have been long-forgotten, because they are not politically correct.

The guy I’m talking about in the Mooreman photo did not turn to run after a gunman, but to get away from what he thought was the shooting area.

Do you understand the concept that Dealey Plaza was “bowl shaped”, and that people in different places in the Plaza thought they heard the shots coming from different directions because they were hearing echoes and reflections off the buildings and the curved walls that were on both the North and South knolls? Or is that just too damn difficult for you to grasp?

Two groups said there were NO gunshots on the police recordings, but Democrats on the Committee weren’t satisfied with that, so they hired another sound lab to set up the test firing in Dealey Plaza in 1978.

Reasonable, because the echo-location made possible by the test firings is the only thing that can identify the impulses as gunshots. Before that was done there would be no way to indentify them as gunshots.

Not so. The “gunshot sequence” is out of place. The entire recording reveals the stuck mike was at the Trade Mart. Therefore, that is proof that there are NO gunshots on the recording at all. Are you saying there were 4 gunshots at the Trade Mart too, and they matched echo patterns of gunshots fired in Dealey Plaza a minute earlier?

In August 1978 test shots were fired in Dealey Plaza and recorded for comparison with the patterns on the evidence tape. Because the location of the subject motorcycle was unknown, an array of microphones was aligned along the known path of the President’s escort through Dealey Plaza which was northerly on Houston Street then westerly on Elm Street. A total of 36 microphone locations, spaced at 6 m intervals, were used to record gunshots fired from the southeast corner window of the sixth floor of the Book Depository and from near the corner of a stockade fence on the Grassy Knoll. The HSCA analysts compared the test patterns against the six evidence patterns by aligning the peaks and scoring the degree of match using a binary correlation coefficient (r)...

Test firings were done and recorded with all these different microphone locations. The reason is the echo-corelation. The sound of a gunshot from a specific location recorded at a specific location creates an echo-corelation pattern that is complex and unique for those two positions. Matches are determined by lining up peaks, within the margin of error of the equipment, and are scored.

If the sounds on the DPD tapes are not gunshots then any relationship to the echo-corelation patterns of the 1978 firings are random chance. So you could ask yourself, what are the odds that a random impulse would match the echo-corelation pattern of a test shot? Then you could further ask yourself what the odds are that four of them do? And further, what the odds are that four of them do that happen to relate to consecutive locations along the street with an apparent speed of motion equal to the actual speed of the motorcade that day?

How do you account for the sound labs claim that the motorcycle was BEHIND the limousine during the shooting, then 3 1/2 minutes later it picked up sounds of the lead-car sirens moving toward it and then past it on the way to the hospital, as the motorcade turned off of the Stemmens in front of the Trade Mart? Seems that this latest acoustics reports neglects to tell us that fact that the Channel 1 recording reveals.

How did such a phantom motorcycle pass the motorcade, without picking up the siren sounds, and since the motorcade was traveling at high speed on the Stemmens, which was the shortest route to the Trade Mart?

You say "not so" to my comment, but it is so, and your explanation has nothing to do with the comment I made. Identifying the alleged gunshots in the acoustics studies depends on the echo-corelation. That is a fact. Without the test firings there was no, even theoretical, way to do so.

You've explained before what you believe is on the tapes, and I don't have a problem with that. But at this point it is only what you claim. It does nothing to refute this study.

What we are dealing with here is the acoustical studies. Not what one perceives on the tapes even. Not all the other reasons why there can't have been a shot from the knoll. With these studies and the analysis contained in them. If there was no shot then the acoustics can't prove one. You are obviously convinced there wasn't and that's great. Then help me find the alternative explanation for the data. Don't keep arguing about whether there was a shot on the knoll or not.

I don't. I don't even know that is true. Even if it were it would do nothing to help us see how this study is flawed. It would only reinforce the idea that it must be. It is not just the conclusion that matters, it is how it is arrived at.

All of this was liberal and leftist Democrat politics, back during the Carter years. The JFK "conspiracy" hoax benefits the Democrats more than the Republicans.

Some of the guys on this thread are looking for a "government conspiracy", well, here it is. The last two House Committee sound lab reports were faked, for liberal political purposes.

Give it up fRED... You just put a tinfoil hat on your own head.. And apparently are to frantic to notice.. Sad.

So you could ask yourself, what are the odds that a random impulse would match the echo-corelation pattern of a test shot?

In the first place, figure 1 and figure 2 don’t match. You can not overlay figure 1 anywhere along figure 2 and get a match. The two labs involved picked out different spikes for the “knoll” shot. They disagreed on which spikes were the knoll shot, and now this third guy is pointing out a different spike as the knoll shot. That is unscientific.

In the first place, figure 1 and figure 2 don’t match. You can not overlay figure 1 anywhere along figure 2 and get a match.

The printouts are too poor and there is not enough information for me to even attempt to do a match that way. I don't think it proves anything if the two examples printed to overlay each other, there are possibly other factors involved. Believe me, when I get an audio copy to compare I will be right on trying to confirm those matches.

The two labs involved picked out different spikes for the “knoll” shot. They disagreed on which spikes were the knoll shot, and now this third guy is pointing out a different spike as the knoll shot. That is unscientific.

I think you might have something here, but I still need the audio to pursue it. My thought is that if one were free to select your starting "muzzle blast" point from anywhere along a graph of random noise then it would of course vastly increase the likelyhood of finding a match. The statistical analysis assumes that the starting point is obvious from the graph. If that is not true then the whole thing might be thrown out. But I've never seen the actual audio, so I don't know what it really looks like.

Look, this is not about tin-foil hats. Fred25 has never said all conspiracies are bogus, and I don't think that either. I think our recently ex-President was involved with a criminal conspiracy his entire political life. What this is about is following the evidence. What does it show? There are great many people that are predisposed to believe in a JFK conspiracy, not based on evidence. There are others who know some of the objections raised in conspiracy books who think that somehow proves a conspiracy. Fred25 and others maintain that the evidence points only to Oswald.

Why don't we try to keep our discussions limited to the evidence and the facts and leave the personal attacks out of it? On ALL sides.

If anyone thinks a poster is wrong or even stupid, you don't have to say that. Just show everyone where they are wrong by posting the truth. Maybe we can keep this civil. OK?

Would it be safe to say that those "belt" recordings, done on old-equipment (I would guess pre-1961 technology), of what came thru police radios of that same era, would be considerably less than hi-fi, especially when you add the lo-fi quality of the dictabelt to the lo-fi quality of the police radio? Would it also be safe to say that there is no guarantee that the plastic (or whatever) belt has not deteriorated from its original audio quality (however low that might have been) considering some 37 years of chemical deterioration, etc., and the fact that the playback equipment is also antique? Just how reliable is such an old recording for the very subtle details necessary for this sort of audio analysis??

...Just how reliable is such an old recording for the very subtle details necessary for this sort of audio analysis??

I'm sure we wouldn't consider the quality to be very high, but a poor quality recording will reduce the likelyhood of making a match, even if there is one. It doesn't increase the likelyhood of getting a match. Any noise or signal deterioration introduced is like random noise. That statistical analysis tries to calculate the odds of getting a false match against random noise. Poor equipment will not create false matches.

--but a poor quality recording will reduce the likelyhood of making a match,--

Why don't we try to keep our discussions limited to the evidence and the facts and leave the personal attacks out of it? On ALL sides. If anyone thinks a poster is wrong or even stupid, you don't have to say that. Just show everyone where they are wrong by posting the truth. Maybe we can keep this civil. OK?

Two bits you have never seen the first series of posts on this subject, in Jan.?, --- When fRED was calling everyone in sight, practically everyone at FR in fact, a kook and a weirdo.. Now, he is acting kooky & weird himself..

--The police were using two radio channels for communica–tions at the time of the assassination. Routine transmissions were made over a frequency designated as channel one ... An auxiliary frequency, designated channel two, was dedicated to the President’s motorcade ... for about five and a half minutes between 12.28 and 12.34 pm, channel one transmissions were dom–inated by the sound of a motorcycle with a faulty relay causing the radio microphone to switch open intermittently. About half-way through this particular motorcycle trans–mission there occurs a sequence of static-like noises inter–preted by some listeners to be possible gunfire [4].--

Since the motorcade was using channel 2, and the motorcycle was on channel 1, the motorcycle was not in the motorcade, as a preliminary conclusion. What evidence is there that despite the motorcycle radio transmissions on channel 1 it was nevertheless in the motorcade? Has the particular motorcycle been identified, with an explanation of why its radio was on channel 1?

--... These acoustic analysts concluded that: the motorcycle with the open microphone was in the President’s motorcade ...--

That cannot be a true statement as it stands. Ordinary microphones are not sound level meters. Also, simply tapping a mike can produce what seems like a loud sound through speakers or on a recording. A spike on a recording is not evidence of a loud sound.

--... In this case, the null hypothe–sis is that the acoustic pattern is not a gunshot from the Grassy Knoll, but random noise, --

That is not correct. The null hypothesis is "any other noise," not "random noise." It is not the case that "any other noise" would necessarily be random noise.

--... It seems unlikely that a random process would produce impulse patterns resembling four gunshots from the Book Depository building and one from the Grassy Knoll, all within the space of eleven seconds, and nowhere else on the recording.--

On what basis is that supposedly unlikely? It is not considered good statistical work to assert, "gee, y'know, this sorta seems unlikely."

--... the automatic gain control built into the Dallas Police radio system produced distortion in the signal such that the waveform could not be relied upon for identifying the type of weapon or even if the sound actually was a muzzle blast from a weapon--

That is an overt admission that the evidence recording is only noise, for purposes of analysis. There are no identifiable gunshots at all.

All mentions of gunshots on the evidence tape must be discounted, since there is no actual evidence of any gunshots based on the tape.

--Alternatively, the limiting circuitry does not affect the time history of the incoming signals.--

That's dependent on circuit design. It's certainly possible to chop peaks in a way that affects timing. Did they examine the actual circuit design?

--... The pattern resulting from each combination of shoot–er and microphone location is complex and unique ...--

Not true. Complex maybe, but not unique. Arrival of the initial wavefront will be differently timed for each distance from the source, but echo timings can be duplicated depending on distance and position of reflective surfaces. As an example, consider a microphone placed so that a reflective surface is 100 feet away at 90 deg to the shot. Moving the reflective surface to 270 deg, at 100 feet, would produce the same echo timing, since the distance is the same. The microphone could not tell whether a building is to the right or to the left. All equal paths will produce equal timing. A single (omnidirectional) microphone is inadequate to determine direction.

--... and by applying echo location principles one can isolate the origin of the sound,--

Except, perhaps, for not being able to tell which direction it comes from. That's the only problem.

There is also the question of how omnidirectional the test mikes were. I find no mention of the kind of microphones used in the tests.

The police microphone was not omnidirectional, of course. Such mikes are highly directional. If the analysis treated the police mike as tho it were omnidirectional that was certainly foolish. I do not find any indication they did not treat it so.

Commercial systems do not rely on what's being talked about here, they use widely distributed sound detectors and triangulation. See:

--However, one of these sounds, the first in sequence, consists of only a single, 15 msec duration impulse [17], and was therefore not included among the six patterns test–ed as possible gunshots, even though to the unaided ear it is the sound most like a gunshot.--

"Aural Presentation
"A dispatcher can listen to a snippet of about 6 sec of sound from any sensor to assist in determining the event type: firecracker string, multiple gunshots, shotgun blast, backfire. Trained humans can distinguish the type of event more accurately than is presently possible by a computer using sensor data."

The exclusion of the impulse mentioned above is therefore apparently not well founded. ShotSpotter says the human ear is currently the better judge.

The actual data they have is from 6 meter microphone spacing. In the computer model, however, they pretended to have 0.6 meter spacing. The data is not good enough to support such a model.

For a "typical" sound of 1000 Hz, the wavelength is 1 foot, approx. They pretended to have better than 2 wavelength resolution when they really only had 18 wavelength resolution.

--A perfect match would not be expected even if the evidence patterns were, in fact, gunshots.--

So the only question is how much to fudge the data to get a match. They fussed with it and found the answer.

Here’s an interesting quote from the 1982 National Academy of Sciences report, about why one of the House Committee sound labs tossed out 2 of the six “gunshots” they “found” on the recording.....

“Of the six sets of impulses that give high binary correlation coefficients with test shots, BRSW selected four as likely assassination shots by eliminating those whose echoes were inconsistent with a reasonable trajectory.”

Ok, so the lab claims there are 6 gunshots on the tape, based on studying the waveforms on the print-out. The “acoustics” evidence reveals to them 6 gunshots. However, the timing of two of those shots doesn't make sense, as far as reasonable trajectory is concerned (for example, if the limousine is hidden from shooters by the trees or the roadsign). So the sound lab just tossed out two perfectly “good” gunshots, because the trajectory made no sense at those points in time.

This is one of the most stupid things I’ve ever heard “scientists” do, during a scientific “study”. There were either 6 shots on the recordings, or no shots.

--This is one of the most stupid things I’ve ever heard “scientists” do, during a scientific “study”.--

I completely agree that this seems absurd. The study has a citation (sorry that I didn't post the References) on ruling out the first shot. It cites:

"Barger, JE, Robinson, SP, Schmldt EC & Wolf, JJ Analysis of Recorded sounds relating to the assassination of President John F. Kennedy. Bolt, Baranek & Newman, Inc. 1979. HSCA Proceedings Vol. 8, p.60"

Sorry I haven't responded sooner. Internet at work died this afternoon and was out the rest of the day.

--but a poor quality recording will reduce the likelyhood of making a match,--

Understood, but that doesn't lead to a greater likelyhood of a match, it creates more random noise. A match is defined as a deviation from random noise.

Fred25 was a cameraman and reporter. I am an expert in some things that are not connected to my line of work. The science here isn't that hard.

Since the motorcade was using channel 2, and the motorcycle was on channel 1, the motorcycle was not in the motorcade...

What evidence is there that despite the motorcycle radio transmissions on channel 1 it was nevertheless in the motorcade?

The echo-corelation. Solving for the echo patterns gives the location of the microphone. It isn't determined yet that the motorcycles in the motorcade were on channel two, it is good lead.

True, but probably just imprecise wording. I take it to mean that sounds on the recording are as loud as gunshots on the recording would be.

That is not correct. The null hypothesis is "any other noise," not "random noise." It is not the case that "any other noise" would necessarily be random noise.

On what basis is that supposedly unlikely? It is not considered good statistical work to assert, "gee, y'know, this sorta seems unlikely."

Well, that seems pretty darn unlikely to me too so I don't quible with them over it. However it isn't left at that statement. The statistical analysis is designed to answer how unlikely it is.

Not in this case, it better not be. The whole point is to measure and compare to the test shots.

That is an overt admission that the evidence recording is only noise, for purposes of analysis. There are no identifiable gunshots at all.

No, it means just what it says. The AGC distorts the pattern by chopping peaks, but doesn't effect the timing of the peaks.

All mentions of gunshots on the evidence tape must be discounted, since there is no actual evidence of any gunshots based on the tape.

If the evidence is what they say it is, then there is evidence of gunshots. If it isn't, let's find out.

--... The pattern resulting from each combination of shoot–er and microphone location is complex and unique ...--

Agreed. I thought of that too. What they should have said was the pattern was complex enough, with enough variables, that duplicating one using other positions would be unlikely, but not unique.

--... and by applying echo location principles one can isolate the origin of the sound,--

Except, perhaps, for not being able to tell which direction it comes from. That's the only problem.

Commercial systems do not rely on what's being talked about here, they use widely distributed sound detectors and triangulation.

Echo-location does not depend on the direction of the sound. Triangulation does, but they are different processes.

I do have all the House Committee books, but I’ll have to find them. They are in my garage.

The major difficulty is that they do not have a number for N, the number of peaks on the evidence tape, presuming cavalierly that the recording represents gunshots. There is only one way to get N, and that is experimentally. The procedure would be, to use audio and radio equipment like that in use with police motorcycles at the time, set it up as required, fire gunshots, and see how many good, separable impulses, of suitable amplitude, they obtain from a shot, by using that equipment. Would it be 5 impulses? 10? 15? 20? 50? Repeating the experiment a few times would give an N as the average number of impulses they would expect to appear on such a recording. Or, they could take N as the number of impulses likely to appear under the circumstances, since the recording is not high fidelity, to say the least.

The importance of experimentally verifying N is this: say that such an experiment showed they would expect to find 9 suitable impulses from a shot on the recording. However, in the statistical analysis here being discussed, N is given as 15 (later changed to lower numbers.) What, then, are the other 6? Or, say the experiment gave the expectation of 20 impulses - where, then, are the other 5?

If experiments indicated they should expect 5 impulses to be recorded per shot, then they should look for 5; if it indicated 20 impulses, they should look for 20. The idea is not complicated.

Without real, physical, experimental data for N, the number of impulses to expect on the evidence tape is an unknown number. No legitimate statistical work is possible without a known N.

I've taken a look at the analysis, and at some websites, and I do not find that such experimental evidence for N was ever collected. Does anybody know that it was, and if so, where is it?

The analysis contains the ironic comment: "The matching procedure begins with the alignment of the first peak in each pattern, the impulse corresponding to the muzzle blast. Because these impulses are aligned deliberately they cannot be scored as a match." That comment occurs in connection with the correction of supposed earlier errors.

The irony is that, since there is no true number for N, every alignment perceived is a deliberate alignment. The alignments must be deliberate, simply because, they do not know how many impulses they are looking for. For all they really know, despite the presumption of echoes, the true N for the evidence tape may be only 1. By the logic offered in the quote, none of the supposed matches counts.

Since they did not have a real N for the evidence tape, how did they get such a number? By all appearances they faked it.

They derived N from n, n being the number of impulses on the test recordings, or the number of calculated impulses from the computer model. Using the test or computer-generated impulses, they inferred N by pattern matching with n. N is not from the evidence tape, it is from the test recording or computer model, the same as n is. Correlation is hardly a surprise; they effectively correlated n with itself.

That's really all one needs to know about the quality of the statistics presented.

Again, from the analysis: "By “precise” match it is meant that all 26 predicted echoes on the analytically gen–erated acoustic fingerprint was [sic] matched by a corresponding impulse on the evidence tape to within +1 msec."

Repeating the earlier point for emphasis, what if the actual N for the evidence tape is 10? Or only 1? What, then, are these other matches they claim to have?

That's incorrect. They defined a match as an impulse within a "window." Impulses were matched individually; randomness is not a property of individual items.

--[RR: What evidence is there that despite the motorcycle radio transmissions on channel 1 it was nevertheless in the motorcade?]
The echo-corelation.--

--[RR: There are no identifiable gunshots at all.]
No, it means just what it says. The AGC distorts the pattern by chopping peaks, but doesn't effect the timing of the peaks.--

It means exactly what I said it means. There are no identifiable gunshot sounds, whatsoever, on the evidence tape. That is exactly the fact of what it means.

Beg your pardon? How does one locate a sound without ascertaining its direction?

I've been examining some of the audio from the site Fred25 provided at http://mcadams.posc.mu.edu/dpdtapes/. It looks like the Channel 1 audio does not start when the web page says it does. It says the orange highlighted transcripts are on the audio and the orange starts before 12:30 for Channel 1. But the audio has the phrase "531. Testing 1 2 3 4" only one minute into the recording. That phrase appears more than 3 minutes 45 seconds after 12:30 according to the transcript. That means the relevant section with the alleged gunshots can't be on that audio stream, so I don't have it.

On a different subject. From the same site the Channel 2 audio has this phrase shortly after 12:30, "Have my office move all available men out of my office into the railroad yard to try to determine what happened in there and hold everything secure until Homicide and other investigators should get there." On the audio stream from this site the end of that phrase, "hold everything secure until Homicide and other investigators should get there", repeats three times consecutively, one immediately after the other. Can anyone confirm or deny that this is what happens on the actual recordings?

You are right. The Channel 1 recording on the website starts too late. Either that, or a section has been edited out of it. My timing shows the sirens turning up at about 3 1/2 minutes after the assassination, but that website has them turning up sooner after the beginning of the recording.

I haven’t heard all of that website’s playback of Channel 2, but if there are two or three repeats of one phrase, that was probably due to the Gray Audograph needle skipping backward to a previous groove in the disk, two or three times (as the disk was played back) before the mechanical mechanism of the Gray Audograph finally pulled the needle so far over, it couldn’t skip back again.

The mechanical mechanism gradually and automatically used a worm gear to move the needle during record, and I think it also used the same worm gear to move it during playback too, with a little “play” in the needle so it could seat itself in a groove during playback. However, the needle was capable of skipping backwards a couple of times on playback, into the same previous groove, if there was a slight damage to the edge of the groove. The National Academy of Sciences considered this when they studied the recordings, and I did too, when I worked on my two-channel synchronized version in 1981.

I am in the process of rounding up my best copies of the two Channels and my two best recorders so that I can make a dub of the recordings for you. I should have the dub made by Monday, and I’ll send the tape to you, probably by Priority Mail, so it will get to you faster than the last tape I sent.

I’ll also see if I have a copy of the Gallery record that Gary Mack made. It contains the “gunshot sequence” and also the “hold everything secure” crosstalk by Decker, which Gary and the HC sound labs didn’t notice, until it was pointed out to them by the National Academy of Sciences.

If you hear a slight “pre-echo” on Channel 2 of loud passages, before the passages are actually spoken clearly, that is probably due to “bleedover” from a future groove back to a previous groove, since the plastic disk was so soft. In other words, when a loud passage was recorded, the needle vibrated so much, it impressed some “pre-echo” bleedover vibrations on a previous groove.

If you need some photos of the same type of Dictaphone and Gray Audograph, I’ll try to find mine and photograph them for you.

Note: The “bleedover” on Channel 2 seemed to work in a backward direction only. This is probably because there was only a very thin line of plastic between the last already-recorded groove, and the groove currently being recorded, but there was no thin line ahead of the groove currently being recorded, because that part of the plastic record was still blank and solid. So, the needle, vibrating actively during loud passages, was able to impress slight vibrations on the outside of a previous groove in the soft plastic, but it was not able to impress slight vibrations on a “future” groove, because no “future” groove existed yet.

That is all very much appreciated. Thanks. I will start working on the first radio interview now. Should have a result in a couple of hours.

The following is quoted from an article Steve Barber wrote about his experiences.:

The tape recording Garwin sent was a recording directly off the playback on the turntable-not grey equipment. There was no way I could listen to this tape, and get anything out of it without slowing it down. What I did then was take two portable cassette players, plug one into the other. I took one of them apart, applied pressure to the pinch roller with my thumb, harmonized the 60 hz hum on the recording with the hum emanating from the speaker from the cassette player by slowing the recording down until they were in perfect harmony (remember -- I'm a musician) thus allowing us to hear the speech at the real speed it was recorded that day, instead of too fast or too slow.

Needless to say, I had one sore thumb when I was finished. I sat in one spot, pushing harder and harder on the roller until the recording was finished.

Totalled up, it was about 43 minutes. This however, gives us a totally new recording of channel two without the words and phrases missing and/or skipping/ repeating, and/or speed distortion. But the fun wasn't over yet!! The sound that BBN said was a "carillon bell" on channel one was also occuring on channel two-in the same time sequence-three seconds after Decker finished speaking . However, on channel two it was much louder. It happened at the time on the "Ferrell copy" of channel two (with the skips) when the disc skipped at that point, cutting off this sound plus four words spoken by the dispatcher at DPD headquarters . It proved to me that it was nothing more than interference on the police radio frequency. Not only did this sound occur at 12:31 but a similar sound occurs at 12:45/46 on channel two, again while the dispatcher is speaking into his mic.

Upon discovering this, I immediately called my friend Todd Vaughan and played it over the telephone for him. I Then informed professor Ramsey about it, since in the final chapter in the NAS report, in the "Possible further studies" section, they mention that further testing should be done on the "carillon bell" sound to see if it could be determined what the sound actually is . When I informed Ramsey of this, he responded by stating that he "qualitatively confirms" that it was electronic noise, and people from IBM in New York were going to perform some data testing on the sound.

I was then contacted in October of 1982 (4 months later) by Ramesh Agarwal at IBM in New York who had helped with the NAS study, along with Burn Lewis, and Richard Garwin, They performed some tests on the sound, and determined that I was correct in my discovery of electronic noise. They compared the sound at 12:31 (Three seconds after the Decker phrase on both channels one and two) with the sound at 12:45/46, and said that it was frequency noise. Nothing more. BBN's second mistake. This has somehow gone unnoticed though.

They easily fly off the handle, become infuriated, defensive, arrogant, belligerent, and some times downright violent. In the words of my colleague Greg Jaynes, it's "JFK: The game." And, in the words of Dallas county Sheriff Jim Bowles, "This case wouldn't go to court because of what the researchers have done with the evidence." And with this, I rest my case.

Thanks for the info. I did my “synchronization” copy from what I think is a copy of the “Ferrell” copy. This was apparently made by a Dallas policeman, apparently Paul McCaghren, who had possession of the belts and disks for a while, before he gave them to the NAS, and I got my copy from a professor who said he got his copy in Dallas from Mary Ferrell.

I realize there are skipped words in my synchronized Channel 2, but the synchronization method I used did not need all the individual words. I used the crosstalk segments and the Channel 2 time annotations for synchronization with Channel 1.

I used a university oscilloscope to get the correct speed of Channel 2, since it emitted a recorded 60 cycle hum every time the dispatcher pressed his microphone key. Then I tried to match the Channel 1 speed to the Channel 2 speed.

The synchronized copy you receive might not be running at the exact speed, since I did my synchronization on a 2-channel video tape machine, that had a very precise speed control, but your copy will be made on a battery-operated portable audio recorder.

There is only a small handful of people who really want the "truth" to surface. You can tell this by the reaction you get when you gather evidence to the contrary of their preconceived beliefs that Oswald didn't kill President Kennedy.
They easily fly off the handle, become infuriated, defensive, arrogant, belligerent, and some times downright violent. In the words of my colleague Greg Jaynes, it's "JFK: The game." And, in the words of Dallas county Sheriff Jim Bowles, "This case wouldn't go to court because of what the researchers have done with the evidence." And with this, I rest my case.

How droll, mlo.. Above, you 'rest your case' on your own vaunted impartiality.. And on your own request at post #2..

Like many, I had no 'preconceived' beliefs in Nov. 63.. But then the WC Report finally was published, and I read the official single bullet theory.
-- The jacket/shirt back wound photos did not match the autopsy diagrams of the neck wounds.. I wrote a published letter to the SF Chronicle to that effect in late '64.. Many others came to that same conclusion at that same time..
Then, when reinactments using the Z film time line estabished that the single bullet had to have 'magical' properties, -- only THEN, I came to the conclusion I now hold..

Oswald certainly could have fired the bullet that killed JFK..
But there was no single bullet that hit JFK in the back, exited his neck, & hit Connelly..

Thus, - I cannot believe in magic. It is highly unlikely, almost impossible, that Oswald could have made all those wounds ALONE..

-- I also find it highly amusing that you, fred, redwine, shooter, etc., -- think that only critics of the WC report hold preconceived notions.. Your posts here are full of them.. And more.

How droll, mlo.. Above, you 'rest your case' on your own vaunted impartiality..

I took me a minute to figure out how you could possibly miss the attribution that I gave, then I realized you must have taken the "..." line as a sign that the quote was finished and what followed were my own words. They weren't. The "..." indicated I was skipping over some text. All the words belonged to Steve Barber, including the "I rest my case" paragraph.

I went and looked at post #2 in this thread. I don't see a request. What am I missing?

Like many, I had no 'preconceived' beliefs in Nov. 63.. properties,...only THEN, I came to the conclusion I now hold..

The key is how willing you are to modify those beliefs in the face of evidence you didn't know before or because of new understanding. Many people cling to a belief once they arrive at it despite incredible amounts of evidence to the contrary. Some will never give up a belief no matter what. Many don't understand how to rationally consider evidence and how to arrive at a logical conclusion. They look at some facts and come to a feeling about what is going on.

But there was no single bullet that hit JFK in the back, exited his neck, & hit Connelly..

Here's the problem. This is admittedly counter-intuitive. It doesn't seem right. But the evidence indicates that it did in fact happen, and there are explanations of how it could happen that do stand up to rational criticism, no matter that people find them hard to believe. So the question is, which is more important? The feeling that this is somehow magic, or rational thought?

-- I also find it highly amusing that you, fred, redwine, shooter, etc., -- think that only critics of the WC report hold preconceived notions.. Your posts here are full of them.. And more.

I can only speak for me. I find it amusing that you can say I "think that only critics of the WC report hold preconceived notions." If you have been paying attention you would see that is not true. People on all sides can have preconcieved notions, and do. If I do have a pre-concieved notion that I am not aware of, tell me what it is and back it up. I will listen.

There is a part of me that wished we could prove a conspiracy. It is just more interesting that way. I had the same reaction to the OJ case. I was hoping all along that they would show that the cops really did plant the evidence and he was framed. I have a healthy disrespect of authority, and it would just be more fun. But that didn't happen. The evidence said he did it, and I will always go with the evidence. The same applies to this case.

I went and looked at post #2 in this thread. I don't see a request. What am I missing?

How cute. - OK, - no 'request', an observation that this tread should be about acoustics. --- Then you post Barbers preconceived BS.. Yep, hard to 'see' that..

Like many, I had no 'preconceived' beliefs in Nov. 63.. properties,...only THEN, I came to the conclusion I now hold..

The key is how willing you are to modify those beliefs in the face of evidence you didn't know before or because of new understanding.

-- Indeed. That one of my main points here.. Freds crew are insisting they have 'new' evidence.. I see none..

Many people cling to a belief once they arrive at it despite incredible amounts of evidence to the contrary. Some will never give up a belief no matter what. Many don't understand how to rationally consider evidence and how to arrive at a logical conclusion. They look at some facts and come to a feeling about what is going on.

But there was no single bullet that hit JFK in the back, exited his neck, & hit Connelly..

-- NO. The evidence does NOT show 'that it did in fact happen'.. This is your biased, 'preconceived belief'. Nothing more.

So the question is, which is more important? The feeling that this is somehow magic, or rational thought?

-- I also find it highly amusing that you, fred, redwine, shooter, etc., -- think that only critics of the WC report hold preconceived notions.. Your posts here are full of them.. And more.

However difficult it may be for you to believe, I am objective. I don't hold an opinion at this time as to whether there was a conspiracy or not. I have in the past been sure there was, but I have learned to be a little more critical of claims made by conspiracy authors. My objective analysis of the evidence regarding the actual shooting is that there is no credible evidence that any shots came from other than three shots from Oswald. There are questions about some things, but no other evidence. That doesn't mean there was no conspiracy. It is possible a conspiracy was involved in getting Oswald to do the deed, involved in the reason for the assassination, and in covering-up some things. I have seen things in just the past few days that made me wonder, but I have also seem some really absurd conspiracy analysis. There is much more of the latter. There is a part of me that wished we could prove a conspiracy. It is just more interesting that way. I had the same reaction to the OJ case. I was hoping all along that they would show that the cops really did plant the evidence and he was framed. I have a healthy disrespect of authority, and it would just be more fun. But that didn't happen. The evidence said he did it, and I will always go with the evidence. The same applies to this case.

The 'underlined' makes my case.. You have 'objective analysis', the rest of us have preconceived beliefs.. Yep, fer sure.

I went and looked at post #2 in this thread. I don't see a request. What am I missing?

How cute. - OK, - no 'request', an observation that this tread should be about acoustics. --- Then you post Barbers preconceived BS.. Yep, hard to 'see' that..

It was a legitimate question, I didn't know what you were talking about. I could have asked in some insulting manner like you do, but I didn't. There is no need to be a jerk.

-- Indeed. That one of my main points here.. Freds crew are insisting they have 'new' evidence.. I see none..

I'm sorry, but I don't recall Fred's crew (what crew?) saying they have 'new' evidence. They have been saying the EXISTING evidence supports a single gunman.

Then you do acknowledge having them. I invited you to tell me what mine were and support a contrary view. You didn't.

-- NO. The evidence does NOT show 'that it did in fact happen'.. This is your biased, 'preconceived belief'. Nothing more.

I'm afraid there is a lot more. The HSCA eventually decided there was evidence for a conspiracy, right? That tells me that they were not predisposed to support the Warren Commission, they were willing to find a conspiracy, some say eager, if they found evidence for it. Yet even they didn't dispute the single bullet theory or that Oswald fired all the shots that caused damage. The fourth shot they decided missed. The reason is that the evidence DOES support the single bullet theory. People can question certain aspects, it can seem strange and unlikely, but the totallity of the evidence says it happened. That is NOT my preconceived belief. My preconceived belief, had I one, would be that the single bullet theory is not true, just as yours is.

I can only speak for me. I find it amusing that you can say I "think that only critics of the WC report hold preconceived notions." If you have been paying attention you would see that is not true...

The 'underlined' makes my case.. You have 'objective analysis', the rest of us have preconceived beliefs.. Yep, fer sure.

I didn't say that either. Many people do have preconceived beliefs, true. I don't make generalizations about the "the rest" of you. Your underlined quote doesn't make your case, it shows that you don't know the differences in methods of arriving at a conclusion, which is what I was talking about. One is not unobjective because they come to a conclusion. Science comes to conclusions all the time. What matters is how the conclusion is made. If it is made based on the desires of the person for a certain answer, or their political leanings, or their preconceived ideas, or without considering all the evidence including evidence to the contrary, then it is not objective. In science conclusions are also always open to re-examination with new evidence or better understanding. My conclusion is based on my knowledge of the evidence and my objective analysis. I do not claim it is the final truth or that I am infallible. If there is evidence I am not aware of I would like to know about it and I will take it into account. I know how I think, you do not. You can assume that everyone that disagrees with you is intellectually dishonest if you like, but you would be wrong.

What don't you try discussing the evidence that proves your opinions, instead of attacking other people?

I have given a great deal of thought to the acoustics study, as you've probably figured out. It is a difficult challenge.

The conspiracy people already think I'm part of the Warren Commission support system. Fred thinks the acoustics aren't worth worrying about because the other evidence disagrees with it and there is reason to doubt its validity.

I could easily jump to one side or the other. I have a scientific study here that claims to come just short of proving a fourth shot from the grassy knoll. On the other hand, I have lots of reason to think the study is fatally flawed. I haven't done either because, despite tpaine's disbelief, I really am interested in figuring out what really happened and I don't care which way the answer comes out. The problem is, whatever the truth is, it should account for all the observations, not just part of them. I am not happy with any explanation that leaves uncomfortable facts hanging. I want to offer a summary of my thinking on this so far, partly to hit the highlights of the topic, and partly because I have an idea, a working hypothesis, that just might go a long way to getting an answer. I want to see what you think of it. I'll come back and post something in a little while.

My main server is down. I have only one hour per day on my backup. I mailed the audio tape today via Post Office Priority. It should take about 4 days to get to you.

"The conspiracy people already think I'm part of the Warren Commission support system. "

Letter from Warren Commission General Council J. Lee Rankin to Warren Commissioner John J. McCloy (President of the Chase Manhatten Bank and a man with no experience as a homicide investigator) in which he makes it clear that the Warren Commission is not only biased towards the "Magic Bullet" but not reporting all the evidence that contradicts the theory.

You claim to have 'objective analysis', while the rest of us have preconceived beliefs.. Yep, fer sure.

-- There you go again! -- I somehow don't know how to arrive at conclusions, while YOUR conclusions are 'objective analysis'.. This is sophistry on your part. - Hubris to the point of being humorous.. Much like fRED.

I do not claim it is the final truth or that I am infallible. If there is evidence I am not aware of I would like to know about it and I will take it into account. I know how I think, you do not. You can assume that everyone that disagrees with you is intellectually dishonest if you like, but you would be wrong. What don't you try discussing the evidence that proves your opinions, instead of attacking other people?

Fred started his "JFK - KJB leftist infiltrators on FR" bull back in January.. We 'discussed the evidence' til fred gave up in February or so.. When he came back with this series and the same old bull, he refused to answer my objections directly, useing innuedo to attack, as you saw a few of his posts ago..

Now you can assume that I am assuming everyone else is dishonest.. That in itself is a false assumption on YOUR part..
But the only thing that IS clear in the JFK assassination, IMO, is that the WC Report evidence is flawed.. And that is ALL I have been claiming from the start of this teapot tempest, put on by a crackpot..

Oh, boy, these guys are really convincing, huh? Have any of them sent you any copies of the Oswald interviews or the DPD tapes? Have they posted any links to rare documents about the assassination?

This is your own acoustics thread, and now you’ve got two trolls trying to mess it up by posting unrelated pictures and propaganda on it. These guys don’t even bother to start their own threads.

I've already answered Rivero and I'm not going to continue the personal debate with tpaine. He can continue the discussion on the acoustics or not, as he chooses. I hope he does.

I couldn't get back on earlier than this to post what I wanted to because my internet service at work was down again. I have some ideas that I think are interesting. I want to present it right though. There is something I need and maybe you can help me find it. I need to look at the NAS study that refuted the acoustics. I don't know exactly what or where in it, but I think there is something in there I need to see. Do you know an online source for it? I am also going to need to examine the recording of the alleged gunshots, so I hope you can get that tape off soon.

tpaine isn’t worth the time of day. He offers nothing of value, he posts no documents, and he repeats his same rants over and over and over again. I don’t know what his problem is. Maybe he’s just going senile. The guy has an obsession with being noticed and observed and thinking that he is the webmaster for these threads, and he seems to think he is the Emperor of the World. He reminds me of old Emperor Norton of San Francisco.

I will make a copy of the NAS report and send it to you. (Or, Ha! Why don’t you try to get a copy from the great know-it-all, Emperor Tpaine!)

I guess it will be easiest for me to photocopy the report and mail the copy. If you know what particular section you need fast, I can post a few pages, but it takes me a long time to post a single picture to photopoint.

My server was off for several hours today too. What are we all going to do if we have a big war and all our electrical power goes off!?

_Jim told me earlier that he was able to download both audio files and they played just fine on his machine, but I haven’t been able to load and play them yet.

This is a quick summary of what I see as the significant findings of the Thomas report. My goal, what I would like to see, is an explanation for these findings and of the other relevant evidence that satisfies all the facts. This is central to the scientific method and that is how I approach things. A scientific theory needs to explain all the relevant observations, not a selected subset of them. It can't ignore contrary evidence. Right now, neither side of the debate satisfies those criteria. However, if you believe in rationality and cause and effect, there must be some true explanation not in conflict with the facts.

After listing each major finding I will make some comments about it. Where its weaknesses may be, relevant information, ideas, questions, etc. Please feel free to add your own ideas and comments.

1. A re-examination of the timeline and of the "crosstalk" instances support the placement of the suspect impulses as occuring at the time of the assassination gunfire.

Barber comments on this recently saying the study only allows 1 second after the final gunshot for Decker to say "go to the hospital." Witness and photo evidence disputes that. However, the timing is elastic enough to allow a few more seconds at that point if we assume the tape speed deviated in the right direction. The tape speed was not constant and is known to have varied.

Are the match criteria too loose? How different can a waveform be and still qualify as a match? Allowances are made for the poor quality of the equipment and the limiting ciruitry and the microphone placements for the test shots. Are the allowances so generous that false matches are generated? Matches could also be coincidental matches with a non-random cause that makes similar patterns, at an unkown probability.

3. The suspect impulses do not appear at other places on the recording. There are five good matches to test shots, with one rejected for non-acoustical reasons. Other impulses were rejected for acoustical reasons.

That there are multiple impulses that do not appear at other places on the recording indicates that they ARE NOT RANDOM. If they are not random they had a cause. Impulses that are excluded are problematic, because the impulses are grouped together in time their cause should be related. A match that is rejected for non-acoustical reasons is even more troubling. If the analysis says this looks like a shot that we know did not happen, then that makes the analysis suspect. Since the signal is there, the match parameters and the echo-location parameters need careful examination.

4. A statistical analysis calculates the probability of the impulses arrising from a random source. That probability is too low to be accepted as the explanation.

The statistical analysis is based on a comparison to a random signal. If the signal is not random then the statistics are not valid. An unknown cause is not the same as randomness. The grouping of the impulses at one place in the recording indicates a non-random cause. If that unknown cause naturally generates impulses that are similar to the alleged gunshot impulses then the statistical probability of a match increases drastically! What is this cause?

5. The order of the echo-located microphone positions indicates successive positions on the street at the right speed.

This finding is dependent on the precision of the matches. If those standards are too loose then we should find that a given impulse creates matches at multiple microphone locations.

Decker said “hold everything secure” about a minute after the assassination, as you will hear from my raw tape, my edited tape, and the Ramsey tape. My edited tape is running at the most accurate speed.

The gunshot sequence is clearly identified in Gary Mack’s record, which he played raw once, and during which you can hear Decker’s crosstalk remarks. Then Gary superimposed real gunshot sounds over the raw recording.... two shots before Decker’s crosstalk, and two shots after Decker’s crosstalk. Gary and the House Committee never noticed the crosstalk until after the NAS began talking about it. I heard it on the raw recording about a year before that.

I maintain that if you do a straight oscilloscope “wiggle” print-out of all the stuck mike sequence, you will find thousands of “spikes” that resemble the “grassy knoll” spike.

The “signature” of a crude gunshot recording is simply 1 large spike (the supersonic shock wave), followed immediately by another single spike (the muzzle blast), followed by other identically shaped but smaller spikes (the echoes). You can search an oscilloscope print-out of the entire stuck mike sequence and find thousands of spikes, big ones followed by little ones, and little ones followed by big ones. But in the Thomas report, the print-out of the DPD “knoll” shot, from the DPD recording, is missing the shock-wave spike.

I think the two House Committee sound labs, at the insistence of conspiracy buff Robert Blakey (the liberal Chief Council to the Committee), who wanted to publish a conspiracy book about his work with the Committee, either faked their reports or did a very sloppy job with them. Two other HC sound labs found “No” gunshots, while the two liberal labs claimed they found 5 or 6 gunshots. They threw one or two of them out, for non-legitimate reasons, and they claimed that 4 were valid (because most of the conspiracy buffs had already settled on 4 gunshots as the Politically Correct number), but they were so unprofessional, they never bothered to synchronize the two tapes to find the exact timing of the assassination on the Channel 1 recording. I think they produced a liberal Democrat hoax that they felt would be in the “best interest” of the country. LOL, this wouldn’t be the first time that government contract agents lied to the American people.

Blakey went so far with his own hoax, he played a “sound” version of the Zapruder film on NBC in 1981 that contained 4 gunshots, and Dick Cavett announced that the “sounds we are about to hear” were recorded by the DPD in 1963. Even though Blakey knew that the sounds were actually recorded in 1978, and he says so in his book, but he didn’t correct Cavett’s introduction and he misled millions of Americans that night on NBC. That is the type of phony liberal media “conspiracy” hoax that has led many Americans over the years to believe in a “conspiracy”. They fall for this type of hoax, and the information goes into their minds and stays there.

Only one out of 280 million people, me, bothered to: 1) synchronize the two recordings, 2) record the Blakey NBC hoax on video tape, 3) buy a copy of Blakey’s book and see that he said the shots on his “sound version” of the Zapruder film were actually recorded in 1978. And what I am competing with here are some of the 279,999,999 million other people who have never done what I did to investigate and expose Blakey’s hoax.

Many FReepers know the Democrats lie. They know the liberal media lies. Yet many of them fall for many Democrat and liberal media hoaxes regarding the JFK assassination, and they try to lecture me about how I am wrong about technical subjects that I spent an entire career and lifetime learning about. They are victims of the liberal media hoaxes, yet they are condemning me for trying to expose some of those hoaxes.

But I support your investigation, and I’m anxious to learn about your final conclusions.

Fred25 isn't worth the time of day. He offers nothing of real value, yet imagines that he does. His latest, this acoustic thing, will prove nothing. Flawed acoustic recordings interpreted by biased minds equal = zip..

He is posting documents that have no bearing on how oswald alone could have shot JFK without a 'magic' bullet. He just insists he did , and he repeats his same rants over and over and over again.

I don't know what his problem is. Maybe he's just going senile. The guy has an obsession with being noticed and observed and thinking that he is the webmaster for these threads, and he seems to think he is the Emperor of the World. He reminds me of old Emperor Norton of San Francisco. He certainly is one in 280 million, I'll give him that..

I’m going into town today to make a copy of the NAS report, then I’ll send the copy to you.

Boy, this crackpot we have on this thread is really nuts, but he helps to show what kind of people support the “conspiracy” hoax.

Let me know when you get the DPD audio tape. You should have it by Saturday or Monday at the latest. I sent it by Priority mail. That means the package will sit in my Post Office for a couple of days, before it is shipped, and it will sit in your Post Office for a couple of days, before it is delivered.

Boy, this ~~crackpot~~ [tpaine] we have on this thread is really [driving me] nuts, [because I can't refute his reasoning].

But he helps to show what kind of people support the ~~"conspiracy" hoax~~ [case against the WC Report whitewash of the JFK killing]..

Hey, I just figured out how to copy the NAS report as a text file, using my scanner. Here are the two index pages.

I made the photocopies of the complete report, and I’ll try to get them in the mail tomorrow.

Do you want me to convert and post some more text before I send the photocopies out to you?

By the way, I call this the “NAS” study, but some people call it the “NRC” study. (National Academy of Sciences, National Research Council).

At the time of the assassination of President Kennedy the Dallas police recorded sounds from an open microphone; these sounds have been previously analyzed by two research groups at the request of the House Select Committee on Assassinations. Both groups concluded with 95% probability that the record- ings contained acoustic impulses which provide evidence for the existence of a shot from the grassy knoll area of Dealey Plaza. On the basis of these re- sults and since shots definitely were fired from the Texas School Book Depository, the House Committee concluded that "scientific acoustical evidence establishes a high probability that two gunmen fired at President John F. Kennedy".

In response to a request from the Department of Justice, the National Research Council Committee on Ballistic Acoustics has over the past year studied these reports and the Dallas Police recording on which they are based. Since the recorded acoustic impulses are similar to static, efforts to attribute them to gunshots have depended on echo analyses; but in these analyses desirable control tests were omitted, some of the analyses depended on sub- jective selection of data, serious errors were made in some of the statistical calculations, incorrect statistical conclusions were drawn and the analysis methods used were novel in some aspects and were untested at such high levels of background noise. Furthermore, some of the recorded background sounds, such as the delay in the sounds of police sirens, are not what one would expect if the open microphone had been in the motorcade. For these and other reasons discussed in the report, the Committee concluded that the previous acoustic analyses do not demonstrate that there was a grassy knoll shot. The Committee reached this conclusion prior to the availability of conclusive evidence (which we now describe) that the acoustic impulses were recorded on Channel I approxi- mately one minute after the assassination.

Following a suggestion volunteered by Steve Barber of Mansfield, Ohio, that the acoustic impulses are overlapped by an almost unintelligible voice transmission on Channel I which might be identified as cross talk from Channel I!, the Committee had sound spectrograms made of the appropriate portions of both channels. Copies of these sound spectrograms and analyses of them are included in Section IV of the report.

The sound spectrograms show conclusively that the portion of the Channel I recording with the acoustic impulses also contains a weak recording on Channel I of cross talk from Channel II of a message broadcast approximately one minute ifter the assassination. The Committee has examined the possibilities that the :::hannel II cross talk might have been overrecorded at a later time on top of the Channel I acoustic impulses or that the Dictabelt examined was a copy with cross talk superposed during copying. The Committee concluded that such scenarios not only are highly contrived and unlikely but also are contrary to physical and acoustic evidence, such as the effect of Channel I heterodyne tones in sup- pressing cross talk from Channel II. This identification of cross talk between Channels I and II shows conclusively that the previously analyzed sounds were recorded about one minute after the assassination and, therefore, too late to be attributed to assassination shots. A similar conclusion is reached independently by the analysis of the times of the acoustic impulses of intelligible cross talk between the two channels more than three minutes after the assassination. This analysis shows that the previously studied acoustic impulses were recorded after the motorcade was instructed to go to Parkland Hospital.

The Committee report lists a number of possible further studies of the Channel I recording and of related matters, but, because of the strength of the demonstration that the acoustical evidence for a grassy knoll shot is invalid, the Committee believes that the results to be expected from such studies would not justify their cost.

For these reasons and for others given in detail in the report, the National Research Council Committee on Ballistic Acoustics unanimously concludes that:

o The acoustic analyses do not demonstrate that there was a grassy knoll shot, and in particular there is no acoustic basis for the claim of 95% probability of such a shot.

o The acoustic impulses attributed to gunshots were re- corded about one minute after the President had been shot and the motorcade had been instructed to go to the hospital.

o Therefore, reliable acoustic data do not support a conclusion that there was a second gunman.

Luis W. Alvarez, Lawrence Berkeley Laboratory, University of California [Nobel Prize winner]

Richard L. Garwin, Thomas J. Watson Research Center, IBM Corporation,and Adjunct Professor of Physics, Columbia University

Alfred Johnson, Bureau of Alcohol, Tobacco, and Firearms, National Laboratory Center, Department of the Treasury

Robert A. Phinney, Princeton University Charles Rader, Lincoln Laboratory, Massachusetts Institute of Technology

(The views expressed in this report do not necessarily represent those of the home institutions of the participants.)

C. K. Reed, Senior Advisor, Commission on Physical Sciences, Mathematics, and Resources

Bertita E. Compton, Special Assistant, Commission on Physical Sciences, Mathematics, and Resources

What is that old saying about a horse designed by a committee, fRED?
But in any case, this IS a fine list of outstanding members of the establishment and committeemen par excellence.. ---- All handsomely paid [one way or another], for their biased 'conclusions', I'm sure..

I'm sorry, I have been unable to get on the internet all day. Don't worry, it has nothing to do with our efforts. Hopefully I will have access tomorrow during the day and can deal with this. If not it will have to wait until tomorrow evening. Sorry for the delay in answering questions. It couldn't be helped.

Ok, don’t worry. Maybe we need to take a little break anyway. I hate it when ISPs go down!

Do you want me to convert and post some more text before I send the photocopies out to you?

What I'm looking for right now is any mention or reference to what other possible sources there might be for the "gunshot" sounds. I have reason to believe there is such a reference. If you can find that and scan it, it would be helpful.

Mlo, have you even been reading what your partner fred here is posting? The man is mad as a hatter.. He claims to be 'competing' with 279,998 BILLON people.. Below:

Only one out of 280 million people, me, bothered to: 1) synchronize the two recordings, 2) record the Blakey NBC hoax on video tape, 3) buy a copy of Blakey's book and see that he said the shots on his "sound version" of the Zapruder film were actually recorded in 1978. And what I am competing with here are some of the 279,999,999 million other people who have never done what I did to investigate and expose Blakey's hoax.

Thank you for continuing to reveal the mindset of the JFK conspiracy cultists. You're doing an excellent job of it.

--What I'm looking for right now is any mention or reference to what other possible sources there might be for the "gunshot" sounds.--

Do you understand that the recording contains a lot of static, engine noises, crosstalk, etc.?

I sent the Report to you yesterday morning by Priority mail. You should have it by Monday or Tuesday. I’m busy now making copies of the Oswald tape and other tapes for other people.

Do you understand that the recording contains a lot of static, engine noises, crosstalk, etc.?

Yes I do, but it can't be written off that easily. Those noises occur all througout the tape and the suspect signals don't. It is very tempting to say it's just noise, but all of the studies actually considered that. They based their statistical analysis on the probability these signals would occur in random noise. The lowest probability, calculated by the NSA panel, was a 78% chance that they were NOT noise. The point is, there is a signal there. It needs explaining. The new Thomas study corrects statistical errors on the prior studies and arrived at the figure of a 1 in 100,000 chance the signals were noise.

Remember the point #4 from my summary. "The statistical analysis is based on a comparison to a random signal. If the signal is not random then the statistics should be different..."

This is a quote from the new Thomas study, "If the source of the impulse patterns was some non-white noise the distribution of peaks might be non-Poisson and therefore have a different probability. However, the NRC panel offered no evidence nor suggested any non-white noise phenomena that might account for the impulse patterns."

Right there in his own words, he agrees with me. So you can see how important the question is of whether we can deduce an non-random cause for these signals. If we could simply postulate a plausible non-random cause, the 1 in 100,000 chance statistics are immediately invalid and tossed out.

John McAdams emailed Charles Rader recently about the new acoustics study. McAdams is the person that runs the website that Fred25 posted earlier with the actual sound clips from the recordings. Rader is an acoustics scientist and one of the members of the NSA panel. This is a quote from Rader's response.

"Thank you for continuing to reveal the mindset of the JFK conspiracy cultists. You're doing an excellent job of it."

My 'mindset' simply disputes the single bullet theory of the WC Report.. On the basis of rational facts published in that same report..

You people can play with these side issues, in attempts to 'prove' there were only three shots, for instance.. That's fine.. But IF you do so, you still cannot explain how a single gunman could have made ALL the wounds in the Z film time frame, with the three shots as theorized by the Commision.

The magic bullet is theoretical bull.. The theory has to be established as based on fact. That is impossible, due to a botched government investigation..

--They based their statistical analysis on the probability these signals would occur in random noise.--

What makes you say that? The spike noises you call the “suspect signals” look the same as thousands of other spike-signal noises that are scattered throughout the several-minute recording, except for a few different voices and heterodynes. We can hear the microphone bumping something. We can hear the motorcycle revving up and slowing down. We can hear clicks and clacks, which would show up in an oscilloscope view as a group of spikes, just as the “knoll” shot appears, but with extra noise spikes mixed in (just as the Channel 2 print-out appears).

I can’t find that “78% chance” quote you mentioned. Are you sure it is a real quote from the NAS study, or did Thompson make it up? The NAS said the microphone was NOT in Dealey Plaza during the assassination, so how could the 5-6 spikes be caused by “gunshots”. Were there shots at the Trade Mart too?

The new Thomas study corrects statistical errors on the prior studies and arrived at the figure of a 1 in 100,000 chance the signals were noise.

How could the signals NOT be noise, if the microphone was NOT in Dealey Plaza at the time of the assassination? Certainly there weren't two shootings, one minute apart, one in the Plaza and the other at the Trade Mart, with 4-6 shots fired at each shooting.

I’d like to see your print-outs when you have produced some from the original recordings. Let me know when you receive my tape and the copy of the report.

I am trying to do something serious here. It is certainly possible I can miss something or make a mistake, but a comment like that is not helpful. If you think I'm not understanding something, tell me what it is. I am doing my best to deal with the facts here and I've gone to considerable trouble to explain myself. I am asking for help from anyone that can provide it. Nobody has to participate, but something more than a comment like this is needed if you do.

There are repeated statements in the Thomas study making the point that the statistical analysis is based on a comparison to random noise. I quote:

"...A conservative estimate of the true value of the probability that the putative Grassy Knoll shot is attributable to random radio noise is no greater than 0.037."

"...giving a final number set of {86,10,8,6} which has a p of 1.12 x .00005, or, 100,000 to one, against. Thus one can conclude that the resemblance of the impulse pattern on the Dallas Police tape to the echo delay pattern of a gunshot from the Grassy Knoll was unlikely to arise from a chance array of radio noises."

"...With a rigorous statistical analysis one arrives at a calculatoin for the probability that the recording contains a random pattern which by chance resembed the acoustic signature of a gunshot from the Grassy Knoll at no more than p = 0.037."

"...If the source of the impulse patterns was some non-white noise the distribution of peaks might be non-Poisson and therefore have a different probability. However, the NRC panel offered no evidence nor suggested any non-white noise phenomena that might account for the impulse patterns."

The reasons I say that are, various comments from the Thomas study and the other reading I have been doing of other discussions about these issues. I can only summarize the discussions I've read by saying that nobody, critic or defender, has disagreed with the idea that they only appear at this one place on the tape, grouped together. There is various text in the Thomas study that says this, like, "...It seems unlikely that a random process would produce impulse patterns resembling four gunshots from the Book Depository building and one from the Grassy Knoll, all within the space of eleven seconds, and nowhere else on the recording."

Now I don't hold this as gospel. I haven't had the entire tape until today (thank you very much!) and even with it the task of scanning it all for similar signals seem daunting. One would think that previous panels like the NRC would have looked and reported them if they found them. If someone can claim these "echo-patterns" exist in other places that would certainly be important information. We can't determine this from simply hearing the tape though.

I can’t find that “78% chance” quote you mentioned. Are you sure it is a real quote from the NAS study, or did Thompson make it up?

The 78% comes from the Thomas paper and he gives a citation for it. The citation is,

"National Research Council, Committee on Ballistic Acoustics. Prepared for the Department of Justice, Washington D.C. Report No. PB83-218461, p. 16., 1982"

Of course I have not confirmed this since I don't have the report yet, but I doubt he would "make up" a citation. If you have this can you check it?

--I am trying to do something serious here. It is certainly possible I can miss something or make a mistake, but a comment like that is not helpful.--

It will be helpful if it gets your attention. :-) There are some things you need to know, if you do indeed want to take this seriously.

I wrote you a rather long message to which I do not find a response. Do you recognize the importance of the number of impulses per supposed pattern on the evidence tape?

--There are repeated statements in the Thomas study making the point that the statistical analysis is based on a comparison to random noise.--

I'm sure that's all very nice, but the comparison was to an echo pattern, not to "random noise." The evidence tape was compared to an echo pattern, to many echo patterns, I should say. That's the actual comparison that was made.

The way you're characterizing this, it is not clear you apprehend what was done.

There was not a comparison of the evidence tape to random noise; the evidence tape was compared to echo patterns. Conversely, the echo patterns were compared to the evidence tape, whatever the evidence tape's character might be, random or otherwise.

The HSCA researchers took a segment on the evidence tape, compared that with a segment of gunshot echo pattern, and looked to see how may impulses lined up so as to be considered a match. That's the comparison.

I have already written you a rather long message on a particular and significant point. See my msg #61 above. Perhaps you would wish to respond to that now, or at least take a look at it.

It's important you understand about the number of impulses expected, because I've now located and read the HSCA testimony of Dr. Barger, and I find he and his associates were indeed cognizant of the importance of the number of impulses to expect on the evidence tape, and applied, or at least claimed to apply, a preliminary test having to do with exactly that. (Whether they properly applied their own preliminary test is highly dubious.)

I believe you're aware the analysis you posted is dependent on the earlier results from HSCA.

It's a serious question whether Dr. Barger and his colleagues gave due weight to their own preliminary tests. Would you say that 20 is approximately "about 10," but 1 or 2 is not approximately "about 10?"

Perhaps you might agree it could be significant if the HSCA study did not faithfully observe its own preliminary tests.

However, there's no point in continuing on that issue until we have an understanding about the importance of the number of impulses to expect on the evidence tape.

Concerning noise on the evidence tape, one of your earlier comments was incorrect. A greater amount of noise, random or otherwise, increases the probability of a match. That can be seen by considering the extremes. A noiseless tape, with no impulses at all, would of course not give any matches at all. A tape so noisy it graphs as solid black would give a match at any position. More noise of any kind = greater probability of a match.

I can only summarize the discussions I've read by saying that nobody, critic or defender, has disagreed with the idea that they only appear at this one place on the tape, grouped together.

Hey, what about me? I disagree. And I think you’ve found my comments and observations to be accurate so far. I don’t have the time to go over every page of the NAS report, since it’s 96 pages long.

There is various text in the Thomas study that says this, like, "...It seems unlikely that a random process would produce impulse patterns resembling four gunshots from the Book Depository building and one from the Grassy Knoll, all within the space of eleven seconds, and nowhere else on the recording."

Did Thomas give you a print-out of an oscilloscope-type readout of every other section of the recording? I don’t think he did. He’s just telling you what he thinks about one small section, and he wants you to take his word for it. I’m giving you the complete recording.

I thought he first said there were patterns resembling five gunshots? But he just threw one out, because it was inconvenient and Politically Incorrect. So which is it? Four or five? How can he arbitrarily throw one out? Which one? Why that one? Why not any of the other four? Why not just toss a coin to decide which one to throw out? His methods are not scientific.

You say he quotes page 16 of the NAS-NRC report about the “78% chance”? Here is the pertinent quote from page 16............

“These errors are discussed in Appendix A, where it is shown that, with these corrections and a conservative adjustment, a significant level as high as P = 0.223 can be obtained for the hypothesis of random location; this value is much less impressive than the BRSW/WA value of 0.05. Furthermore, as discussed previously, even if it were granted that the hypothesis of randomly located impulses on relevant portions of the tape were in serious doubt, it would not follow that the alternative of gunfire from the grassy knoll was convincing. All plausible alternatives to both of these hypotheses would have to be eliminated, and no convincing effort has been made in this direction.”

This section is discussing the BRSW/WA mathematical manipulations, which were incorrect. Appendix A discusses this in more detail. This has nothing at all to do with what the NAS thought the “probability” of gunshots actually was. The NAS actually thought the probability was “0”, because the NAS thought the microphone was not in the motorcade. Regarding the “78%”, the NAS was discussing the numbers manipulation methods used by BRSW/WA. See NAS-NRC Report, Appendix A, Page 40. In the NAS quote below, Thomas converted the number “.223” into the number “78%”.......

Moreover, two of the predicted echoes appear in one window. Thus 10 coincidences among 12 predicted echoes and 14 impulses out of 45 windows should be adjusted to 8 coincidences among 11 predicted echoes and 12 impulses out of 90 windows. If we now reduce the number of concidences by 7 to make a conservative adjustment for the "free" parameters, we would have 1 coincidence among 4 predicted echoes and 5 impulses out of 83 windows. The hypergeometric probability calculation would then yield a significance level of P = 0.223, which is not at all impressive in contrast I to the claim that P = 0.053. However, this adjustment may be unduly conservative.

(1) The BRSW/WA conclusion of a probability of 0.5 of a shot from the grassy knoll on the basis of the BRSW analysis is invalid as is also the conclusion of a probability of 0.95 for such a shot on the basis of the WA analysis.

(3) Except for the rather conservative analysis above, the data do tend to cast doubt on the hypothesis of random impulse locations according to a Poisson process.

(4) Alternative hypotheses to a random Poissson process and a shot should have been examined as possible explanations of the .coincidences. These might invoke the nature of the bursts of noise prevalent during the period under study and a consideration of other possible non-Poisson distributions.

How many people, other than you and I, and how many Washington Post reporters, are ever going to go into this much detail in studying both the NAS and the Thomas Report? In the meantime, the Washington Post article has already been read by millions of people, and it will be posted on many internet JFK assassination websites. This is how propaganda works. The Thomas “study” is merely a bunch of mumbo-jumbo, designed to get liberal media like the Washington Post to print “conspiracy” propaganda stories for consumption by the naive and gullible American public.

Where are all the “conspiracy” buffs on this? Are they studying the actual recording, the NAS Report, and the Thomas Report? Or, are they just passing along the Washington Post report?

Look, I thought we had a deal. I would send you the Oswald interview tapes, and you would put them on the internet so everyone could hear them. Then I would help you with the acoustics study.

But no one now can play the version of the Oswald interviews you posted, so I would appreciate it if you would straighten that out first, and then get back to the acoustics stuff later.

I’ve spent a lot of time and money on this project during the past few weeks, and I would appreciate it if you would post the Oswald interviews as we originally agreed about. I’m getting all sorts of FReep mail from people who are waiting to hear the Oswald interviews.

I don't know a thing about sound so this is my only post that I'm going to make on this thread.

tpained, you had 7 threads to prove that the single bullet couldn't work and you spent it all in personal attacks and mindless drivel. All of your posts could have been cut and pasted over and over because you never said anything original. Now this thread is working strictly on the sound evidence and Fred even stated that it is NOT for the other evidence. So if you can't provide anything to refute that evidence, why don't you simple go away and leave these people alone?

To anyone else on this thread that would like to see an end to the personal attacks from this person, complain to the webmaster, because this behavior has gone long enough.

-- Nonsense.. Back in Jan., fred gave up on his defense of the magic bullet.. These threads are just more BS agit-prop from him in an effort to mitigate that failure.. AND some more of his self puffery, of course..

Now this thread is working strictly on the sound evidence and Fred even stated that it is NOT for the other evidence. So if you can't provide anything to refute that evidence, why don't you simple go away and leave these people alone?

-- I didn't respond to this thread till #45, when fRED started up on his conspiracy hoax BS once again.. Every post since then has been in defense of my original position..

To anyone else on this thread that would like to see an end to the personal attacks from this person, complain to the webmaster, because this behavior has gone long enough.

-- And you, redwine, & mlo, in defending freds 'KGB/marxist conspiracy hoax' mania about JFK, are also contributing to this silly crackpot tempest..

--How many people, other than you and I, and how many Washington Post reporters...--

All of your posts could have been cut and pasted over and over because you never said anything original.

LOL! I told him that very same thing! I also pointed out that he never posts any original articles of his own, that get more than about 5 or 6 responses, and when I said that to him, he accused me of being someone else who told him that very same thing two or three years ago! LOL!

This guy is just plain nuts. He must not realize how stupid he sounds, repeating the same things over and over again. He’s repeated his same stupid “single bullet theory” posts at least 20 or 30 times. He copies and pastes some of our own posts into his posts, making his posts longer than they need be, then he complains because these threads get too long! LOL! What an IDIOT!

I don’t remember what I said back in January!! Anyway, I probably didn’t have intelligent people like Shooter, Red, and mlo on that other thread, who understand ballistics, photography, and acoustics.

Well, I have a background as a journalist, and it drives me nuts when a major newspaper publishes incorrect information that is read by millions of people. That is one reason this country is in such a mess today.

By the way, mlo finally posted the Oswald interviews to a good workable website, and I passed the link along to several people, who have reported back to me that they have successfully downloaded the recordings.

I want to thank mlo for his efforts. And I’m sorry if I irritated him by nagging him so much.

Thank you all for your work on this and the other threads. I can certainly understand the exasperation, too.

There have been so many false scents laid on the trail of the long-ago truth that taking wrong turns is always going to be part of the hunt for the facts of the case. I am afraid it was planned that way.

For example, I read a very well written book by a former Secret Service man, (Title of Book and Name of Author in Alzheimer Land) in which he laid out a perfectly plausible and rational scenario for the shot that struck JFK's head from the front. He said it was from an accidentally fired M-16 in one of the lead cars. The driver lurched the vehicle at the sound of the first shots, throwing the holder of the M-16 off balance.

If true, it would certainly answer a lot of questions, ballistically, acoustically, and forensically,

Oswald did plan for the blame to be put on the right-wingers. He laid many false scents along his own trail, and he was very clever at it, such as by ordering the rifle under an assumed name, even before he knew who he might shoot with it, should a future opportunity arise. But he made mistakes. We must piece this case together little by little, inch by inch, fact by fact.

It’s much easier for us good ol’ Southern boys to figure this case out, because we can better understand how he thought. You Ohio guys might have some difficulty understanding Oswald.

Oh, it's not mumbo-jumbo. It has some severe deficiencies, but it's generally comprehensible.

An interesting facet of the original HSCA effort is the number of comparisons they made. They compared 432 test patterns to each of 6 evidence tape patterns. Barger said each evidence tape pattern had about 20 potentially-qualifying impulses. He allowed that in the course of permitting "about 20" to be approximately "about 10."

The number of impulse comparisons, then, was 432 * 6 * 20 = 51,840, aproximately. So, from almost 52,000 attempted impulse matches, they ultimately managed to find four candidate patterns. That's persistence. I wonder if they billed by the hour.

With 12 milliseconds allowed per impulse on the evidence tape, and 432 attempted pattern matches, the total time allowed for pattern matches was 5.2 seconds, if my arithmetic is awake this morning. Notice that's half the length of the interval they examined, which was stated as 10 to 11 seconds. They set things up so there was a 50-50 chance of finding a "grassy knoll" shot no matter what the evidence tape showed. At the end of it all, Barger stated the chance they had found a grassy knoll shot was, you guessed it, about 50-50.

Hey, Red, the reason I call it “mumbo jumbo” (other than the fact that I’m lousy in math), is because the recording gives ample evidence that the motorcycle and microphone weren’t even in Dealey Plaza, they were at the Trade Mart. There are no siren sounds on the recording at all, until the motorcade begins to pass the Trade Mart. There is not even a sound of the motorcycle’s own siren, indicating it was never turned on.

Thus, any attempt by any group of professors to monkey around with “probabilities”, “Poisson numbers”, “root-mean-squares”, and “chi-numbers” of the “clack” and “clatter” spikes produced by the wobbling microphone, must be “mumbo jumbo”. In other words, it’s mathematical “double-talk”, professorial scat-talk, sham, and sophistry. They might as well be looking at a geophysical seismograph recording, searching for four or five “gunshot patterns” 300 feet below the surface of the earth, or looking at a fisherman’s sonar print-out, searching for “gunshot patterns” amid the school of fish.

I can just hear the professors now.... “Oh! Here’s one! At the 125 meter level! Oh look, there’s another one, up around 25 meters, right next to that barracuda!” “No, no, I think that’s a small school of sardines.” “Yeah, well, maybe, but my chi-number calculations place the chance of it being a gunshot and the chance of it being a school of sardines at exactly 50-50.” “Well, that’s good enough to go with, let’s inform the Committee and alert the media. The Congressmen and the public will never understand what we’re talking about, anyway.”

Shooter to tpaine.... All of your posts could have been cut and pasted over and over because you never said anything original.

--- 'Mojo' used to have the same odd reaction to my article posting history as you do fRED.. Weird.. but you aren't mojo.. Not smart enough..

This guy is just plain nuts. He must not realize how stupid he sounds, repeating the same things over and over again. He's repeated his same stupid "single bullet theory" posts at least 20 or 30 times. He copies and pastes some of our own posts into his posts, making his posts longer than they need be, then he complains because these threads get too long! LOL! What an IDIOT!

--- And you've kept making this same idiotic response to my critiques, -- how droll..

I don't remember what I said back in January!! Anyway, I probably didn't have intelligent people like Shooter, Red, and mlo on that other thread, who understand ballistics, photography, and acoustics.

tpain said.......... Every post since then has been in defense of my original position

--- Snappy comeback.. Yep. But in effect, you acknowledge defeat in Jan., and claim some sort of triumph on this recent nonsense series.. There is none..

Thank you fRed !... The inadvertant humor of your link is lost on you, fer sure, but I really am grateful..

And I am finally seeing the method to your most recent madness, your 'flagging' me to long threads that I can't access.. This leads me to see what other crazy posts you're making, where I can find your little hidden zingers.. How clever..

But I do wonder, - why not cut the semi-charade of 'ignoring' my comments, and just answer? -- Is it your incompetence, or your cowardice?

I'm responding here because I have no way of telling if my messages are getting through to you on that long a thread.. HTH..

This criticism refers to the calculation by BRSW of probabilities of 0.88, 0.88, 0.50, and 0.75 for the identification of 4 impulse patterns of the DPD tapes as representing four shots. The third pattern is associated with the conjectured shot from the grassy knoll. These claimed probabilities are, at the very least, larger than the BRSW reasoning permit, if that line of reasoning were to be accepted.

In Appendix C, pages C1-C2, of the BRSW report2, it is calculated that the 432 x 4 correlation matches of the 432 echo patterns (derived from the test shots) with the four impulse patterns (on the DPD tapes that were suspected of being patterns from shots) should give an expected 13 false alarms. BRSW found 15 matches, which is within reason. (See Section 5.3 and Figure 22 on pages 60-63 of that report). BRSW applied a 2 x 2 contingency table test based on the data in their figure 22 to decide that the matches are not randomly located and consequently at least ~ of those matches must be real. (See page 66 of BRSW).

We shall comment on this conclusion later, but let us grant this conclusion for the time being. BRSW observe that six of the matches are clearly false alarms. This leaves nine points of which at least two are true matches. We quote BRSW on page 66.

"However, the expected number of false alarms to be found when testing four different impulse patterns is 13 (see Appendix C), and only six have been found. Therefore, it is not unreasonable to expect that there are seven more, although that would be the largest number possible since at least two of the remaining nine are probably detections. The best that can be safely assumed is that each of the nine remaining correlations is equally likely to represent a detection or a false alarm."1

The intended meaning of that last sentence is that each of the nine candidates has as large a probability of being a true match as any other candidate. We would suggest that a conservative estimate of this probability based on the BRSW reasoning would be 2/9. Instead, BRSW apparently misinterpreted their own words, reading "equally likely" to mean that the probability of a false alarm for each detection is 1/2, an interpretation consistent with the somewhat ambiguous language but not with the reasoning.

From their interpretation they proceed to calculate the probabilities 0.88 = 1-(1/2)3, 0.88 = 1-(1/2)3, 0.5 = 1-1/2, and 0.75 = 1-(1/2)2 on p. 67, using the probability 0.5, the questionable assumption of independence and the fact that of the remaining nine matches which are not obviously false alarms three correspond to the first conjectured shot, three to the second, one to the third (grassy knoll) and two to the fourth (see Figure 22 of BRSW report).

Using 2/9 instead of 1/2 would give probabilities 1-(7/9)3 = 0.53, 1-(7/9)3 = 0.53, 1-(7/9) = 0.22, and 1-(7/9)2 = 0.40. These are considerably smaller than the BRSW probabilities.

One may argue that the above calculations are too conservative and that the probability 2/9 should be replaced by a larger number, say 3/9 or 4/9. Certainly the use of 4/9 would be unduly "optimistic" since there are at most four shots.

One must question the reasoning that led to the inference that at least two of the alarms were "true". The 2x2 chi-square contingency table analysis used depends on the assumption of 15 independently located Those alarms corresponded to microphone and rifle locations closely in space. Hence the signals are similar and one should expect that the high correlation coefficients for these alarms are highly dependent An informal study of these locations and Figure 22 would suggest that these 15 alarms are effectively equivalent to fewer, say about 7 or 8, independent points. In that case the significance of the layout is considerably reduced and one may question the conclusion on page 64 of the BRSW report that "the motorcycle was moving through Dealey Plaza and did, in fact, detect the sounds of gunfire." (To be specific, a two by two table with entries 1,3,4,0 yields a significance value P = 0.07, rather than the P<0.01 claimed by BRSW.)

I won't tell you what this wave form is right now. First, I'd like to get your opinions on its similarities to charts you've already seen. What do you think of this?

Your gif didn’t show up directly on the thread, but I copied its code number and got it to show up separately, then it showed up on the thread when I went back to the thread.

This graph looks like that of a spoken word to me, spoken by a human, with a fairly high level of background noise in the background. As a second opinion, I would say that it could represent some type of “clunking” sound made by some object. There are indications of multiple frequencies contained within the various “spikes”, which suggests that this is NOT a sudden “single tone” sound with accompanying single-tone echoes.

It must be a geocities thing, the link is right but it doesn't want to work like this.

OK. How do you think it compares to the waveforms published in the Thomas study? There you will find a clear gunshot waveform and a waveform taken from the DPD recording that was supposedly created by the same gunshot sound. Disregarding the timing of echoes and such, could the waveform I just posted, if picked up by Channel 1 through an open mic, cause a similar pattern to those in question?

Some things to keep in mind, when picked up by Ch.1 it would have to be superimposed over the background motorcycle noise, and the scale of the waveform I posted is somewhat different. It represents 1/2 sec. and the ones in the report are supposedly 1.5 secs.

Thanks for this note. It makes sense. I was wondering what caused it and hadn't made any specific inquiries yet. It happens many times on the section of channel 2 that I've examined closely so far, all approx. 3.4 seconds ahead of the principle signal. I've learned that approximately 3.4 seconds (depending on the distance the needle is from the center of the disc) is the rotation time of the disc.

The print-out you posted has “side wiggles” (see arrows), which are extra “bumps” on the sides of the up and down spikes. These side wiggles represent different frequencies or “compound frequencies”, such as that caused by the human voice. A muzzle blast does not produce the side wiggles, since “frequency” is not a consideration in a muzzle blast and its echoes. And the DPD print-out section in the Thomas study doesn’t have side wiggles either. However, a microphone “bump” can produce spikes without side wiggles, as in the DPD print-out. Microphone bumps and muzzle blasts don’t have various frequency “side wiggles”. They produce sharp spikes that are caused by the microphone diaphragm going in and out suddenly. These are sudden “volume” spikes, but not “frequency” spikes.

Keep in mind that the Thomas and DPD graphs show mainly the “volume” or intensity of the noise or sound. Only when the side wiggles are present, do spikes depict various frequencies, as in your graph. Your graph is not the same as the Thomas or the DPD graphs. The Thomas and the DPD graphs represent sudden “volume” spikes, caused by different sound sources.

The graph I posted is also a volume or sound intensity graph, just like the graphs published in the Thomas study are. Like I said, keep in mind how the chart I posted might look if it were picked up and superimposed over the background noise on channel 1. Also, I mentioned that the scales were different. The scale makes a big difference in appearance. If I had posted my graph at the same scale as the Thomas graph the "side wiggles" wouldn't be very noticeable. I would have done that, but I didn't anticipate it being an issue. I will do it later.

I sampled the "gunshot" part of channel 1 at over 90,000 samples per second, over twice the resolution of a CD. With all the noise on that recording I wouldn't expect to find clear single frequency sounds, and all the examination I've done to date has not turned up many. Once you can examine the recording at that level of detail you find very low amplitude noise everywhere. I didn't go specifically looking for the "side wiggles" you mention though, so I will examine it more carefully and take your comments into account.

More generally, I find that the shape, timing and overall appearance matches quite well. You could try to do an echo-location with a pattern like that. I don't think it would come up with anything interesting, but this is one particular fragment out of a myriad possible variations. You are correct in that waveform I posted is of a voice, although it is not a clear voice. It is actually one instance of a highly distorted, nearly inaudible and unintelligible voice fragment taken directly from channel 2, with no alteration.

On another topic, I have made arrangements to have the audio files hosted by someone without the bandwidth restrictions we have labored under. Once they are actually in place on the new server I will post a notice here. You will still be able get them through the http://www.geocities.com/jfkdocs page, the link will just point to their new location.

Years ago I worked with optical film sound tracks. If I recorded a single tone, a pure musical note, the sound track would look like a perfect “sawtooth” pattern. But if I recorded two tones, the higher tone would be “attached to” the lower tone. You could see the big sawtooth pattern on the track (caused by the lower tone), and the higher frequency would be attached to the low frequency spikes as a series of “side wiggles”. More complex combinations of tones would have the higher frequencies attached to the sides of the big low-frequency spikes.

A muzzle blast recording or a microphone bumping around recording would look very much like a seismograph recording. Compare this earthquake recording to Thompson’s print-out of the 1978 test shot from the grassy knoll..........

You are correct in that waveform I posted is of a voice, although it is not a clear voice

Well, now, do I know my acoustics or what? No, it’s not a “clear voice”. I would say it’s a midwestern accent, Northern Indiana, age of speaker about 45, heavy smoker, male....... (LOL!).

Well, what else is there to talk about? mlo wants to find out exactly what caused the noise on the Dallas tape, but I don't care about exactly what it is. It's noise on a noisy tape. It doesn't provide the sound of gunshots, to the human ear, and the analysis doesn't hold water, so in this context it's useless.

Well, mlo sent me a long letter explaining what he is doing, so it will probably take him some time. I know how it is. I spent months on this project back in 1981 and ’82. It’s a lot of fun to do it one’s own way, instead of having someone else in another state telling you how to do it.

If anyone has wondered where I went, I've been on a document hunt. The first step needed was to gather all the relevent information that I could. Fred25 has helped out greatly by providing the tapes and a paper copy of the NAS report. I have been able to find just about everything else, I think. I will be adding the documents I've collected to the web page as I format them.

Currently on the web page are the Thomas report and, just added, the BBN Report to the House Select Committee on Assassinations and the Weiss and Aschkenasy Report to the HSCA. These two reports are the starting point in the analysis of the DPD tapes as everything else references them. There is a lot more to be added, pro and con. The NAS report is the only one I have yet to find in electronic form, but I understand that someone is working on that.

Red is gone. He either got banned or resigned. I haven’t heard from him in over a week. I’ll give him another week and then I’ll contact him by mail.

Do you want me to send you a copy of my synchronized edit of the DPD audio tapes and a VHS copy of my timed audio/video study? I wanted to hold back on sending you those until you conducted some of your own independent study.

I wonder if you can put that stereo audio in a real player file, in stereo? The drive from the Plaza to the hospital takes about 6 minutes, and you can hear the sirens come up on Channel 1 at about the time the motorcade exits the Stemmons Freeway at the Trade Mart, which proves that the stuck microphone wasn’t in the motorcade.

The Stemmons is now called I-35E. I wonder if we could make an animated map, showing a blinking dot moving from Dealey Plaza to Parkland, timed to move with the timing of my edited version of the audio. We could start at “Go to the hospital officers” and end at “Keep all these vehicles out of this emergency entrance”, and the dot could be at the Trade Mart when the sirens are heard. Could this be done with a Real Player program, with stereo audio and a map picture with the moving blinking dot?

Actually, I have video of 8mm films and still pictures that cover the entire ride to the hospital, starting with a film taken from the West side of the triple overpass, showing the Presidential limousine overtaking Chief Curry’s car and passing it, just before it gets up on the Stemmons. Such a video/audio presentation has never been made before. I think this would be of great interest to all the JFK researchers.

No, we’ve just been waiting for mlo to do some research. His type of research takes a lot of time, and he didn’t need to be bothered every day responding to these threads.

It’s possible that he might be able to turn his JFK website into the most authentic and scientific on the internet, so I’m for him all the way.

I sent an audio copy of the Oswald interviews to Fester, and he’s going to try to make some taped copies available to people.

Let your friends know about mlo’s website and the audio recordings. We need to get the Oswald interviews out before the public, so they can see what a Marxist he really was.

I’m going to see if mlo can post a stereo-audio Real Player movie of the motorcade’s drive to the hospital from Dealey plaza. This would be the first time all the film and the audio has ever been available, synchronized, in one place. Maybe this will be my last worthwhile contribution to journalism, before I kick off.

Later, I hope mlo will also be able to post some of the Russian “conspiracy” documents. There are probably fewer than a dozen Americans who have ever read the Radio Moscow transcripts, and only a few hundred have ever read the New Times articles.

I’m very pleased to be working with mlo. I don’t know enough about computers to be able to put this stuff on the internet myself, and he seems like a very honest professional dedicated guy.

Well, what else is there to talk about? mlo wants to find out exactly what caused the noise on the Dallas tape, but I don't care about exactly what it is. It's noise on a noisy tape. It doesn't provide the sound of gunshots, to the human ear, and the analysis doesn't hold water, so in this context it's useless.

For what it's worth, I understand your point of view. There are various perspectives one could look at this issue from. One could judge it as an informed lay-person and make a call on what makes the most sense. One could look at it from a legal standard and decide what the preponderance of the evidence showed, or what was beyond a reasonable doubt. If that were the standard I were to apply right now I would probably say that the acoustic evidence does not meet the requirements to show a fourth shot. But there is another way to look at this. What I am looking at are scientific reports and analyses. The standards of science are not the same as legal standards, they are much more demanding. Even if you don't feel the need to have a complete scientific answer, you ought to respect those who are interested in that.

There is a quote from the HSCA findings about the proper standard that should be applied. It is not enough to raise objections to an interpretation of the data, pro or con. Fred25 has raised a number of good questions about the acoustic evidence, and those questions should be answered by any accurate study. At the same time there are arguments on the other side that need to be answered. Here is the quote: "To be sure, those who argue the microphone was in Dealey Plaza must explain the sounds that argue it was not. Similarly, those who contend it was not in Dealey Plaza must explain the sounds that indicate it was."

The fact is, whatever is on the tapes is there for a reason. Something happened to create every sound or acoustic artifact. There is an answer, an analysis, somehow that accounts for ALL the data. So far it hasn't been found. Dismissing the signals as noise just isn't enough because that very possibility is what the HSCA and Thomas studies address and reject. You could possibly prove them wrong on that point, but you actually have to do it, not just dismiss them.

Do I want to find what caused the impulses? Of course. Even if it turns out they really are shots. Because if they aren't shots they need to be explained, just as if they are shots Fred25's objections need to be explained.

I have read through all the information I am making available to you at least once, and have given this issue a great deal of my time and thought. I believe there is room for good work to be done here. It's amazing, at least to me, but we are still arguing about work done over 20 years ago. Nothing really new has been done. At that time the technology was still comparatively primitive. In the Weiss and Aschkenasy analysis they are talking about cutting strings to the right lengths and pinning them to maps of Dealey Plaza to find the echo patterns! Another problem seems to be that people were working out of their disciplines and may have made mistakes. The acoustics scientists were not statisticians, for example, yet much of the findings rest on statistics. I think there is a good possibility of finding some logical flaws in their procedures. I have a list of ideas to persue. I put this information on this forum because others may be interested too, and as a check on and a help to my self. You guys may think of something I don't, or point out a mistake I am making. If you aren't interested in this goal, a fuller scientific understanding of the data, then by all means don't participate. I am not looking for an endless argument over this stuff that has nothing to do with the science. If you are interested in participating in an objective and *impersonal* discussion of the science then I would welcome your input.

Later, I hope mlo will also be able to post some of the Russian “conspiracy” documents.

I am saving the stuff you posted in the six JFK threads to add to the web site. I planned on taking the text you posted for each item and making some sort of narrative out of it. Of course the offer of writing something for the purpose yourself stands open.

I’ll try to write a brief summary later. Let me know when you get ready to post the Russian stuff. Some where in my files, I have audio tape translations of several pages of the Russian book, which tells about Sergei Losev meeting secretly with Garrison during the Clay Shaw trial. I can make typed transcriptions of those tapes. And I think it would be worthwhile to post the Congressional Record document that outlines the leftist activities of Tom Buchanan, Mark Lane, and Harold Weisberg, the first three “conspiracy” authors. In addition, I have a very rare video tape of me interviewing Weisberg, in which he admits to having worked with John J. Abt, the lawyer who Oswald wanted to represent him in Dallas. Also, in the interview Weisberg talks about being fired from the Senate LaFollette committee, and being fired from the State Department in 1947. I have other documents that say why he was fired.

Regarding the sirens and the static. If the stuck mike picked up the motorcade as it passed the Trade Mart, then it couldn’t have been in Dealey Plaza. Since there are no siren sounds before then, the motorcycle couldn’t have been in the motorcade at all. Since we can’t actually hear any gunshots on the Channel 1 tape, we’ve got no evidence at all that the microphone was in Dealey Plaza. Since the Channel 1 “wiggles” contain no supersonic shock wave spike, but the test-shot recordings do, that should be proof enough that the various wiggle groupings on the Channel 1 print-out were caused by “static” and other natural noises. You will note above in my post 139 that the seismograph print-out of an earthquake looks as much like the static printouts as the test gunshot printouts do. But you go ahead and conduct your part of the study your way, because that will give us a second opinion that uses a second approach to the overall study.

By the way, if the 2nd photo doesn’t show up in post 139, just right click on the blank picture, click on “Properties”, copy the URL address, post it in the address box and click on “go”. Once it has loaded, click on “Back” and that will take you back to this thread, and then the photo should show up in this thread.

The synchronized edit is on the audio tape you sent. I have listened to it straight through and it is really interesting. I plan to make it available as a Real Audio file. I would of course be interested in seeing the video you did. There is no urgency to it right now because I have enough to keep me busy for a while, but I would like to see it. I am willing to pay for postage and tapes too if you want. You don't need to carry the financial burden for sending me stuff.

Yes, I can do it in a stereo audio file. In Bowles' rebuttal he has a breakdown of the trip to Parkland. I just put the link to his report on the web site. How does it agree with yours?

I'm sure it would. One of the surprising things, to me, about what I've found so far is the real lack of further analysis or experimentation done since the NAS study. Given the interest this case has and the number of people who spend their time on it, I would have expected a lot more work since then. Your ideas are good. How about a computer simulation of the acoustics in Dealey Plaza so that you could run firing tests from other locations? There is nothing terribly difficult about that, it would answer a lot of criticism, and we have the actual test shots to calibrate it with.

Another idea is to do a virtual reality modeling of Dealey Plaza, including the limo and it's occupants, and the shots, to demonstrate the physical relationships involved. This is not something I am prepared to do. I do know of someone who did this, but what I would like to see done with it is to place a vantage point in the model at Zapruder's position and then generate a series of stills of what he would see there in the model. Those could be compared to the actual film and would verify, or not, the accuracy of the model.

Get over it guys. When we pass through those Pearly Gates, God, or one of his subordinates, will tell us what really happened. Until then, we'll just have to wait in Limbo, not knowing. Those of us who don't make it to the Pearly Gates will probably spend eternity not knowing, as just a minor part of our punishment.

Say, I’ve been to Limbo. That’s just north of Lompoc, isn’t it, on old 101?

Don't know. I understand you live in New Mexico. Sort of envy you. I spent July of 1971 in Santa Fe. Beautiful place. Being from the north east,before that I had never seen a sky that was blue all the way down to the horizon. I hope it is still that way.

One night I camped out at the old Indian ruins of Chaco Canyon, very remote from any town. I slept in the back of my camper. I woke up in the middle of the night and I looked out the window, and I thought, “What the heck is that bright light!?” It was like the whole sky was lit up and casting shadows on the ground. So I opened the back of my camper and looked out, and what I saw were millions of stars. No moon, just stars. But they were so bright, they were lighting up my campground a little, and casting shadows.

Chaco Canyon is in the so-called "four corners" vicinity? My wife wants to visit the Anastazi ruins. We will probably do a trip there in the relatively near future.

As you may or may not know, the HSCA did attempt deal with these issues in their findings. You probably won't agree with their conclusions, but all possibilities must be considered. This is what they had to say:

I have been working on adding all the supporting material I could find on the acoustics issue to the web site. I have each of the significant scientific reports, except the NAS report, and several other articles and studies. There will probably be a few other things added over time, like various versions of the transcripts and some related, but not critical, articles, but the important stuff is there. If I find the NAS report online I will certainly link to that too.

I've been reading these things as I find them and I've got lots of questions and ideas. I'm going to spend some time to systematically go through everything to make sure I know exactly what each one is saying and to check the details. If anyone here is really interested enough in this subject I would reccomend reading all of the papers. Once I complete this next step of absorbing all this information I am going to have some specific items to discuss, maybe even before I get all the way through. Of course, if anyone else would like to bring up something we can talk about that too.

On a different subject, you all remember that Fred25 sent tapes to me of Oswald's interviews and I digitized those tapes into Real Audio files to post on the internet. We had initial problems with bandwidth limitations and free hosting services and I had to look for alternative solutions. I have made an arrangement with someone interested in the subject, and with large bandwidth available, to host these files. You can still get them from the links at www.geocities.com/jfkdocs. This allows as many people as want to, to download these interviews, and it allows us to make their availability known to others. If you have not listened to these interviews you should. They are very interesting, even to conspiracy minded people.

Do you think the bullet streaks on the pavement, from officially-unaccounted-for shots, fit in with this interpretation of the acoustic evidence?

The first shot missed the occupants of the limousine. I think the curb was hit early in the Zapruder film.

On online version of the NAS Report has just been made available and I've included a link to it on the page at JFK Docs.

In addition, some of you may know that President Johnson recorded many of his phone calls and that those recordings are available. Included in the available calls are ones he made regarding the Warren Commission. Most of them are calls made to persuade the various members to take part. One interesting call was one from Hoover where they talked about the Commission and some of the evidence involving Oswald. An interesting, and possible useful, fact about these calls, that relates to our subject here, is that they were also recorded on a Dictabelt. These are much cleaner recordings than the radio traffic is but that makes it easier to see what noise and imperfections are introduced by the equipment itself. The link for these is Johnson tapes.

Thanks very much for your information. You are putting some good documentary stuff together all in one place.

I sent Red Redwine a letter, and he finally sent me an email. He has been on vacation. I’m going to try to get him to re-join the board, since he is a sensible person.

untrue...the man in the tower told the Warren commission he DID see something funny behind the knoll, but the commission lawyers didn't care to hear that and went right on...his name was Lee Bowers and he was questioned more in the Mark Lane filmed version of "Rush to Judgement". He died shortly thereafter in a car accident.

"Here’s Zapruder’s view of the fence. Don’t you think he and his secretary would have seen and heard a gunman firing 2.4 meters West the corner of that fence? (This view is to the West.) There was a guy on that sidewalk, and three guys on the steps just to the left of this picture. "

initially, that is where both Zapruder and Marilyn Sitzman, his secretary, said the shots came from...that is why right after the shooting, everyone is seen running towards the grassy knoll...and so is the lone motorcycle policeman...and that is where the closest ground witnesses, the Newman's said the shots came from. It was only later when the LHO lone nut scenario became mantra that people's recollections (some, not all) began to change.

You are absolutely wrong. Go read Zapruder’s testimony. Zapruder was just a few yards from the fence, with a clear view behind it, and he saw nothing there. Stop making stuff up. People did NOT run up on the knoll right after the assassination. Films of the event show people going up on the knoll a couple of minutes after the assassination to see if they could see the Presidential limousine on the Stemmens freeway. Ask Red Redwine. I sent him a copy of a tape of the various films taken in the Plaza after the assassination. The cop ran up in response to Sheriff Decker’s call to “get men into the railroad yard... and see what happened up there”, which was broadcast about a minute after the assassination. The cop saw nothing behind the fence and ran on up to the triple overpass. Red has a copy of that film too. Ask him.

Yes I had read of the man in the railroad tower and as for the something "funny" he saw, he did not see a sniper. There were people BEHIND the grassy knoll and people ON the grassy knoll and they didn't see or hear anything of that sort. The simple fact that, with the confusion, the high buildings in all directions, the motorcycles backfiring, and so forth, a lot of people weren't sure where the shots had come from. Some were clearly confused by echoes or by motorcycle noises.

&nsbsp As an example of how desperate some people were to bolster a grassy knoll theory, someone went through one of the home movies and found a single frame that included the fence, enlarged it beyond all recognition and claimed to seem someone with a gun behind the tree; the image was so grainy and vague that it was almost certainly nothing, except, if this was a person, he was wearing a sort of German WW1 spike helmet and carrying a strange sort of rifle with a barrel bent around like a tuba (Dr Seuss style) and "hiding" behind a tree which, when examined in person or in better photos, was only about 6 inches thick. Yeah, that's the modus operandi of a high class assassin! Oh, and this mysterious - and certainly inconspicuous - person wasn't to be found in enlargements of the movie frame immediately before or after, so he appeared for 1/32 of a second and then vanished utterly. Anybody who can pull that stunt deserves to get away with it!

The Moorman photo of the police radio recording shows 5 distinct peaks ; clearly none of these is an echo

The Moorman photo of the police radio recording shows 5 distinct peaks ; clearly none of these is an echo.

Me either. I found some maps and some aerial photos. The photos may be useful for direct measurements of distances, but I don't have a scale, and I will probably need more precise measurements than I can determine from a small photo.

The point of this is, I have created the algorithms for computing an echo pattern given any set of gun and microphone locations. Of course I have to have precise measurements of the plaza to get good results.

An interesting point arises about this, even without actually doing the simulation yet. Imagine a gunshot at point A and an echo bouncing off a building being picked up by a mic at point B. If you measure the echo path (the distance of which gives you the time delay) you have to choose a point along the face of the building to measure from. The face of the building presents a range of choices, one end to the other, which would give a range of possible path lengths.

When W&A did their analysis they cut strings to the length needed to match the echo they were looking for, then they anchored them at points A and B and found where they echo path (string) touched a building facade. From reading their report it appears they were satisfied as long as a string touched the building. The problem is that not all points on the facade are valid. An echo between points A and B would bounce off the building at the "specular reflection point" which is the point on the building facade where the angles of the path approaching and leaving the facade are equal. If you allow any point along the facade to count as a match then you are introducing an illegitimate margin of error into the matches. They would have had a larger window in which to find "valid" matches.

I'll re-read their report carefully to see if they dealt with this, but I thought you might be interested in the concept.

Try these. The second one has a scale in the bottom right corner, but I can’t read it.

“Mr. WEISS - A survey map; that is correct. The scale was 1 inch corresponding to 10 feet in Dealey Plaza. We used a long graduated ruler that could be extended to measure long distances on the map. We used a hand calculator for computing some very simple things, and we used a device, an electric device called an oscilloscope, for observing the wave shapes of the sounds that we got when we played back tape recordings, and also a device that enabled us to plot these patterns on paper so that we could examine them in very fine detail.”

Your second link above is an image of the survey map that W&A used. That would be perfect if I could get a good quality scan of it. Did you scan that image from your HSCA books?

Is this the same map? This is two pages in “6 Seconds in Dallas”. Map by “Robt. H. West County Surveyor Scale 1” to 10’”

If you contact the County Court House, maybe they can send you a full-sized copy of this map.

This thread has been dead for a while, but there is going to be some news on it soon. Stay tuned.

new thread software bump

As promised, Dr. Thomas gave a presentation at the JFK Lancer conference this past Saturday, Nov. 17. He has written it up and made it available on the internet. You can find a link to it at the bottom of my page of acoustics documents. Here

This is not yet the end of the story.