track 23 unused to prevent interference with the audio.

In the late 1970s and 1980s, digital multitrack tape machines emerged, including the 3M and Mitsubishi X-800 32-track machines, and Sony DASH PCM-3324 and later the PCM-3348 machines, which allowed greater flexibility with more available tracks for recording. As well, in order to mix using automation on the console, analogue recorders generally required adjacent tracks to the time code track to be kept blank to avoid the time code signal interfering with the audio signals, which