Using 16 or 24 track tape machines (especially later in the ‘70s with desk automation requiring 3 tracks - one for SMPTE time code and 2 for alternating desk automation data) the often usual process we used was to record drums, bass, guitar and guide Vox, guide brass/horns - then comp the drums down to a stereo drum track. Then do guitar overdubs - lead, lead solos and rhythm and comp those to a stereo guitar track. Then say horn section recorded individually and comped to a stereo track. Then lead vocals and BV’s - comp BV’s to stereo. Each set bounced to stereo allowed further use of tape compression plus the necessary benefit of freeing up tracks for the next stage of recording. This double use of tape knocked a lot of the hard top end edge off recordings and the mix was part done as you went. Drums in some studios were recorded in an iso-booth in the main live room - one studio I worked in had a floating drum booth on a concrete slab with timber walls and glass window panels and an opening door also with an open ceiling to bass trapping overhead. This decoupled the drums from the rest of the room and gave a really tight drum sound. There was a live area with marble floor - the whole room was L shaped - live with overhead trapping on one arm of the L, drum iso booth at the junction and par-dead on the other arm with rough stone wall for diffusion, windows to control room and overhead and wall trapping. This allowed the whole band to record in the one room - guitar and bass amps isolated with mobile panels.
Mixdown was often using DBX 160’s or 1178 for stereo drum bus - this could be done in the bounce of the drums to stereo to free up the compressors for later use, 1176 or LA2A and Pultec EQP1A for vocals, Massenburg GML8200 and 1178 or 2254’s for main mix bus, mixed to 2 track 1/2” tape master. The mix tape was then sent to the vinyl cutting studio for mastering to vinyl.
