How did music producers physically cut and glue together audio tapes before digital recorders were invented?

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To my knowledge, before the use of computers in audio recording, to cut out errors etc. producers had to physically cut the tape from the analogue recorder and glue it back together. Especially the last part I can’t really comprehend. How do you glue together two loose ends of a tape without any overlapping exactly at the right place and without hearing any errors, stutters or something on the final recording?

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> before the use of computers in audio recording, to cut out errors etc.

If you’re talking errors in a player’s performance, you can have that player do an overdub (or “punch”) that part by rewinding the tape, playing it back up to the point where the mistake was, starting recording then, and then stopping recording at some point after. The playback and the recording were independent operations, and a separate magnetic tape head achieved each.

Multitrack analog tape would allow you to do this for selected tracks only, leaving the rest of the tracks untouched. The engineer or producer could manually choose where to punch in (start recording) or punch out (stop recording) by pressing the record button. As the technology improved over time, the option to program the punch in and out points and automate the punch became available. After analog tape but before computer recording, linear digital tape formats like ADAT or Tascam’s mini-DV one (whose name escapes me) could do the same thing.

A skilled engineer would be able to punch at places where either the player was not playing, or where the other tracks masked any change in level or tone if the punch occurred mid-note. You’d always go back and listen after punching to be sure that it sounded natural. If it didn’t, you’d re-do the punch and coach the player to try to match the sound of the existing part. Or you’d decide to re-take a whole section of the song.

All of this happens while you still have the instruments on separate isolated tracks, before the song has been mixed. In analog tape world you might record the raw tracks on a 2″ 24-track reel-to-reel tape machine, then mix to a separate 1″ or 1/2″ stereo tape. Splicing the multitrack tape was more of a rare occurrence, and I never did it myself. If you wanted to take a section out of the song, it’s easiest with the final mixdown.

You have a reel-to-reel machine and likely some headphones. You play the tape up to the point where you want to make an edit, mark the start point with a marker, find the end point and mark it, then use a razor blade to cut those points and cellophane tape to tape the splice together. The marker and cellotape go on the outside part of the audio tape, where the magnetic film isn’t. You can also disengage the motors that drive the reel hubs and manually spin them to slowly “scrub” through the audio to find a good place to splice. You have to get used to hearing the slowed down audio and knowing where a splice won’t be too apparent.

Because of the nature of magnetic tape, being an analog representation of the signal, and also due to the speed with which it passes over the tape head, 15 inches per second or more for professional machines, the edit doesn’t click and pop like edits in the digital realm do. You’re inducing a current on the electromagnetic playhead, and that current doesn’t immediately change when a sudden change is encountered on the tape- there’s an inertia to it, and the edit is a razor thin line in a medium that’s moving past the head at 15 ips or more.

Source: I worked in a small recording studio just as they were phasing out the analog reel-to-reel machines and transitioning to computer based DAW recording. I don’t have the most experience working with analog tape, though perhaps I’m the wordiest at describing it, so I’ll gladly accept corrections from those who _really_ know it.

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