For all of you who were Elvis Presley fans, and perhaps especially for those who were not particularly his fans, this site tells you why he was so popular from a purely musical standpoint.
“Elvis Presley has been described variously as a baritone and a tenor. An extraordinary compass- the so-called register-, and a very wide range of vocal color have something to do with this divergence of opinion. The voice covers two octaves and a third, from the baritone low-G to the tenor high B, with an upward extension in falsetto to at least a D flat. Presley’s best octave is in the middle, D-flat to D-flat, granting an extra full step up or down. Call him a high baritone. In “It’s'now or never”, (1960), he ends it in a full voice cadence (A, G, F), that has nothing to do with the vocal devices of Rhythm and Blues and Country. That A-note is hit right on the nose, and it is rendered less astonishing only by the number of tracks where he lands easy and accurate B-flats. Moreover, he has not been confined to one type of vocal production. In ballads and country songs he belts out full-voiced high G’s and A’s that an opera baritone might envy. He is a naturally assimilative stylist with a multiplicity of voices - in fact, Elvis’ is an extraordinary voice, or many voices”
- Henry Pleasants, in his book “The Great American Popular Singers” (1974)
For a reminder check out his many youtubes.
An example, one of my favorite songs. I could skip the narrative, though.
A very young Elvis