While your Pro Tools hardware allows a fixed number of voices, Pro Tools software allows for additional audio tracks beyond that fixed number of voices. While all of these tracks can be recorded to or imported, arranged, and cued for playback, not all of them can be played back simultaneously.
When the number of tracks exceeds the number of available voices, tracks with lower priority may not be heard. For these situations, Pro Tools assigns priorities to tracks that compete for the available voices. Because there can be more tracks than available voices, Pro Tools provides multiple ways of adjusting the playback priority of audio tracks. See
Changing a Track’s Playback Priority and
Freeing up Voices on a Track.
With Pro Tools|HD systems, you can assign specific voices to multiple tracks such that those voices are shared by more than one track. This feature is called
voice borrowing. The combination of playback/record tracks and shared voiced tracks comprises the total number of
voiceable tracks available on a Pro Tools|HD system.
Tracks with higher positions (leftmost in the Mix window or topmost in the Edit window) have priority over tracks in lower positions in a session.
You can also adjust the relative priority of tracks by freeing up the voices of individual tracks, making them available to other tracks in the session.