7.2.9. Routing Audio and Managing JACK Connections
Ardour automatically saves the state of JACK connections when it saves a session.
Ardour offers the following output ports, assuming a stereo (two-channel) setup:
two channels per track, called "track_name/out 1" and "track_name/out 2". These will usually be connected to the master bus, or to a sub-mixing bus, when you are using one.
two channels per bus, called "bus_name/out 1" and "bus_name/out 2". These will usually be connected to the master bus, unless you are using two levels of sub-mixing busses.
two channels for the auditioner, called "auditioner/out 1", which represents the channels used to audition a region; when you want to import it, for example, or in the "Regions" box on the right-side, when you select one and right-click and choose "Audition". These should not be connected to the master bus, but to an output device that you want to use when auditioning regions.
two channels for the click-track, called "click/out 1", which represents the channels used to play the click-track when recording. These should not be connected to the master bus, but to an output device that you want to use for the click-track.
two channels for the master bus, called "master/out 1", which represents the output used by the master output bus. These should be connected to an output device that you wish to use for listening to the session when the transport is moving.
Ardour offers the following input ports, for a stereo (two-channel) setup:
two channels per track, called "track_name/in 1" and "track_name/in 2". These should both be connected to the same input device. If you are using a recording bus, then these should be connected to that bus.
two channels per bus, called "bus_name/in 1" and "bus_name/in 2". These should be connected to whatever channels you want to be mixed into them. If you are using it as a recording bus, then these should be connected to the same input device.
two channels for the master bus, called "master/in 1", which represents the input used for the master bus. These should be connected to all of the tracks. If you are using sub-bus mixing, then all of the tracks should connect to the master bus' input either directly or through a sub-bus.
In most setups, Ardour automatically sets the channel connections correctly. There are ways to change the connections from within Ardour, but they offer limited flexibility. For this reason, it is recommended that users use QjackCtl to monitor connections, since through QjackCtl it is also possible to monitor and change many other features of JACK.
Learning to make the right connections is a valuable trick for people using Ardour. The fact that Ardour uses JACK for both its internal and external connections allows tricks such as the earlier-mentioned recording bus (which adjusts the input level of a source), flipping the left and right audio channels, and creating a multi-channel audio output by combining many input channels. Undoubtedly, other tricks exist.
