The instruments were sent to track one and the vocals to track two. The basic tracks were recorded live, with the band playing and singing simultaneously. Then most of the recordings (20 songs of the 28 on their first two albums) received overdubs (add a supplementary recorded sound to a previously recorded performance).
BTR3 Twin-Track (click to enlarge)
The BTR3 Twin-Track was not a true multi-track machine; it did not have independent erase heads, so it was impossible to record on one track while preserving the other. The only way to overdub was by using two twin-track machines; the overdubs were made while the recording was copied to another twin-track machine while at the same time adding more instruments or vocals.
The volume balance had to be set at the time of recording, to facilitate this the engineers would generally superimpose the instrumental overdubs on the instrumental track, and the vocals on the vocal track. So the second generation tape still contained a strict separation between the backing on track 1 and the vocals on track 2 (this made the final mixing into mono easier also).
Beatle albums made using this twin-track tape machine:
- Please Please Me (1963)
- With The Beatles (1963)
(NB the BTR2 mono was used for Love Me Do and P.S. I Love You)