"Heartbreak Hotel" follows a basic eight-bar blues progression, and Presley generally started it with an E chord. In the recording done in the RCA studio he was backed up by his usual trio (Scotty Moore on guitar, Bill Black on bass, and D.J. Fontana on drums) as well as studio musicians Chet Atkins and Floyd Cramer. Both Atkins, a guitarist, and Cramer, a pianist, would go on to have huge careers as musicians and performers.
The musicians were first-rate, but the recording facilities were decidedly not. RCA's Nashville studio had recently relocated to a building on McGavock Street owned by the United Methodists. Not originally designed as a studio, the space suffered all sorts of acoustic problems. Bass player Black, in particular, struggled to find a spot where his low notes would not bounce off the walls.
Nor was the studio equipped to electronically produce the echo sound that Presley had gotten used to while recording at Sun. To replicate it, the crew rigged up an echo chamber in a long hallway by placing a microphone at one end and a speaker at the other and recording the effect live.