A mono audio, Auxiliary Input, Master Fader, or Instrument track controls volume, and, in some cases, panning, for a single channel of audio. A mono audio track uses a single voice. A mono track can also be routed to a multichannel output.
A stereo audio, Auxiliary Input, Master Fader, or Instrument track is a single channel strip for two channels of audio as a stereo pair. Stereo audio tracks use two voices.
(Pro Tools HD and Pro Tools with Complete Production Toolkit Only)
A multichannel track is a single channel strip that plays multiple channels of audio (from 3 to 8 channels at a time). This allows Pro Tools to support multichannel mixing formats including LCRS, 5.1, 6.1, and others. Audio, Auxiliary Input, Master Fader, and Instrument tracks can all use any supported multichannel format.
For more information on surround mixing with Pro Tools, see the following:
