Bouncing tracks down on a limited tape machine permanently fuses them, so sound separation cannot be recovered later

Mills explains that the muddy sound separation on the earliest Underground Resistance records was a direct consequence of bouncing tracks — combining several recorded tracks onto fewer to free up tape channels. Once bounced, the constituent parts are merged permanently: ‘you can’t delete, you can’t take them apart because they’re permanent.’ As he learned studio technique and gained more channels, separation improved. The general principle is that any destructive mixdown (or committing a submix) trades track count for irreversibility — anything printed together can no longer be independently balanced, EQ’d, or muted, so such commits should be made only once the merged elements are final.

Examples

Early UR tracks with poor separation from 8-track bouncing to reach ~24 tracks; later releases sounding cleaner once Mills had more channels and technique.

Assessment

Explain why bouncing/committing tracks limits later mixing control, and state one condition under which committing a submix is nonetheless safe.