“I just purchased a used multitrack analog tape recorder – my first – and have noticed a peculiar thing. Sometimes when I overdub a track, the playback of the track has a delay in it, so it doesn’t sync to the already recorded tracks. My only prior experience in recording is with digital so I’ve never encountered this before. What am I doing wrong?”
It sounds as if you have the track arm switches set to different settings while recording. On the analog recorder there will be switches, one for each track, that allow you to select between three modes (usually, and may have similar or different names): ‘Select’, ‘Sel-Rep’, and ‘Repro’. ‘Select’ arms a track so its ready to record, ‘Sel-Rep’ allows the armed track to be monitored while recording as well, and ‘Repro’ does not arm the track – it just plays it back. Another difference between the playback modes is ‘Sel-Rep’ is actually reproducing a signal from the record head on the recorder, and ‘Repro’ is reproducing a signal from the playback head off of the tape. These heads are a small distance apart from one another – enough distance to account for a signal delay, for instance.
The reason you might be getting a delay? Well if you record a new track in ‘Sel-Rep’ mode (monitoring off of the record head) while listening to a guide track in ‘Repro’ mode (off the playback head), those tracks will be out of sync because of the distance between the heads. The only way for those signals to sync up on playback is for each to then be switched to the other’s setting…that is, if you want to allow for the delay, but you never want to mix (or record) that way. You want your mixdown signal coming from the playback heads – all tracks in ‘Repro’ mode. So the thing to remember is that while recording you should set all of the switches to ‘Sel-Rep’ and during mixdown set them to ‘Repro’. That should eliminate the sync problem.
Many newer analog tape machines have a ‘Sync’ mode so they will automatically play from the same head used to record or automatically switch to Input when armed to record.