Presley goes on to sing spirited versions of tunes made popular by Pat Boone, Chuck Berry, Hank Snow, Faron Young, and the Ink Spots, among others. All these are great fun, no matter how off-key both the instrumental backing and the vocal harmonies tend to be. But the moment I treasure comes about thirty minutes in, when Presley tells the others about an unnamed singer he heard in Las Vegas, who did "a thing on me"' on "Don't Be Cruel." Noting in passing that the singer was "a colored guy" and praising his interpretation of the song as,"much better than that record of mine," Presley remarks that "he had it a little slower than me" -- and then proceeds to demonstrate. Prefacing each chorus with an explanatory "he said," he halves the tempo and gives the song a big finish, as Jerry Lee Lewis gamely pumps away behind him.

But this "Don't Be Cruel" doesn't end there. For the next few minutes Presley keeps breaking into the song every time there's a lull. He gets laughs with his imitation of the black "Yankee" singer's attempt to give the words of the song what the singer must have thought was a genuine southern pronunciation ("tellyphone!" Perkins -- or someone-shouts in amused disbelief). He describes how the singer grabbed the microphone on the last note and slid all the way down to the floor, how on certain lines he shook his head back and forth admonishingly, and how he had his feet turned in "and all the time he's singin', them feet was goin' in and out both ways, slidin' like this." Through all of this you just know that he's illustrating the story by swooping to the floor himself, shaking his own head, and swiveling his own feet.

The unidentified singer who so enthralled Presley (and whom he sounded nothing like) was Jackie Wilson, soon to have hits himself. A month later, as if to prove that imitation really is the sincerest form of flattery, Presley concluded one segment of an appearance on The Ed Sullivan Show with a rendition of "Don't Be Cruel" that, Guralnick tells us, owed everything to Wilson's, "from finger rolls to his pronunciation of 'tellyphone' to the big pumped-up ending."

"It seemed like he had a photographic memory for every damn song he ever heard," Phillips told Guralnick. The venerable music critic Henry Pleasants once characterized Presley as a "naturally assimilative" stylist with a "multiplicity of voices" -- that is, a gifted singer with an instinct for mimicry, whose music incorporated gospel, country, rhythm and blues, operatic airs, vaudeville recitation, and sticky early-fifties pop of the sort that rock-and-roll ultimately savaged.

Pop music as it has evolved alongside audio technology has resulted in what I think of as aural culture -- similar to but finally distinct from the oral traditions on which folk music once depended. Aural culture takes the form of teenagers' uninhibitedly singing along with records (if only in the privacy of their bedrooms) and imitating the sounds on them. Rock-and-roll has been aural culture from the beginning, and the Elvis captured that afternoon at Sun -- already famous, already in movies, perched at No. 1 on the pop charts for the fourth time that year, but still only twenty-one--sounds like a kid emulating the vocal mannerisms of his favorite singers, less for the delectation of anyone who might be listening than for the thrill it gives him to hear those familiar voices vibrating in his own throat. He's his own jukebox.

Although he emulated other singers' styles, Presley was no impersonator. His own personality emerged whether he was singing country, rhythm and blues, or pop. The key to his originality may have been his enthusiasm for so many different kinds of music and his refusal to distinguish among them.