1. In videotape editing, a process or technique employed to (a) enhance (e.g., remove noise from, or introduce some kind of special effect into,) (b) add to, or (c) replace totally, the originally recorded audio (if any,) without modifying the originally recorded video signal. 2. In audiotape editing or mixing, a process analogous to any of the above, performed (a) on a single audio channel, or (b) on one or more audio channels of a multi-track recording without modifying the other channel (s. ) 3. The copying of one or more audio signals from one storage medium, location, or format to another with or without modification or enhancement.