The damage, it seems, is caused not so much by the noise you can hear but by what you can’t hear: the infrasonic waves that attack the balance mechanism in the ear and against which not even home insulation can defend you. Its effects can be felt more than 10km away.
Elephants communicate over long distances by infrasonic sounds. Even elephants miles apart through dense forest can communicate like this.
Last time I observed a Boy Scout gathering at a skeet shoot and not a one of them behaved any differently than any other Boy Scout I've ever encountered. They hit the clay pigeons. The guns fired properly. The boxes of shells didn't fall off the tables and blow themselves up. The windmills continued to turn overhead, silently, majestically, and expensively!
I think the lack of efficiency is where these devices get knocked out of the ballpark ~ the rest of this stuff might be real to someone but ............ I've heard the same stories about SECOND HAND SMOKE!