 RCA's Studio B had recently been equipped with a new three-track recorder. To further improve the recording of Presley's voice, Porter had Telefunken U-47 microphones placed in the studio. The U-47 was the first condenser microphone that could switch between omnidirectional and cardioid patterns. The microphone could be used for vocals, instruments and full area coverage. The first song recorded was Otis Blackwell's "Make Me Know It", which was mastered in nineteen takes. "Soldier Boy" was later recorded in fifteen takes, followed by the non-album cuts "Stuck on You" and "Fame and Fortune". The last song recorded during the March session was a non-album cut, "A Mess of Blues". A new session was arranged for April. Presley then left for Miami, Florida, where he taped The Frank Sinatra Timex Show: Welcome Home Elvis.
