When the loop of the first two tracks (each song needed two tracks for stereo) had been played, the playback head
of the eight-track machine moved down with a memorable clunking sound to the next two tracks, and so on.
I called the Ampex people and told them that I had ruined the playback head
and needed another head.
They became popular because of their relatively small size, their convenience, and the fact that as they were read by a laser beam rather than being physically touched by a stylus or playback head
, they didn't wear out.
They start with a commercially made reel-to-reel tape transport system, then soup it up with customized recording and playback heads
The optical servo is tightly coupled to the drive's recording and playback heads
, allowing for extremely precise positioning of the drive's heads relative to the tape.