The earliest multitrack recorders were analog magnetic tape machines with two or three tracks. Elvis Presley was first recorded on multitrack during 1957, as RCA's engineers were testing their new machines. Buddy Holly's last studio session in 1958 employed three-track recording, resulting in his only stereo releases not to include overdubs. The new three-track system allowed the lead vocal to be recorded on a dedicated track, while the remaining two tracks could be used to record the backing tracks in full stereo.