Audio Busses

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An Audio Bus is similar to a Track, but it does not have the ability to record and play back audio.  Therefore buses have no playlists or regions associated with them.

In some use cases, a Bus is equivalent to a mixer console strip in the traditional analog recording studio.  In other use cases, the Bus is equivalent to the subgroups, auxiliary buses, or master buses of a traditional console.

Due to its nature it is missing the record button and the playlist button.

Typical use cases include:

• Post-processing of Audio Tracks:  one or more Audio Tracks are combined into the Audio Bus for level control, effects, or other processing.
• "Live" inputs which need to be automated or mixed along with other ardour tracks.  A live "voicover" microphone, MIDI synthesizers, or live performance inputs.
• Return paths for external gear such as reverbs or delays.

If you are using Ardour purely as a live "mixer", then you will use only Audio Busses and no Audio Tracks.  More typically, a Bus is used to sum several tracks into a single audio stream which may then be processed and then output again for listening or further processing.