One mark of a good song is that it makes Billboard's top 10 list. An even greater indicator is its staying power; whether it is remembered decades after it was a hit. Perhaps the highest accolade is whether the artist influences other musicians. All of these standards were met by the singing duo the Everly Brothers, one of whom, Phil, has died days shy of his 75th birthday. At age 16 I was a disc jockey for a suburban Washington, D.C., radio station. I hosted a weekend music program called "The Top Fifty Show." The Everly Brothers were always at...