Audio Output preferences let you set the physical output pair on which the stereo output is played, and the surround format. The Output pane consists of the following preferences:
When Show Advanced Tools is selected in Advanced preferences, the following are available:
Stereo Output pop-up menu: Sets the physical output pair on which the stereo output is played.
Mirroring checkbox: Becomes available for all chosen output pairs, with the exception of Output 1–2. Deselect to have the output signal routed to the chosen output pair (Output 3–4, for example). Select the checkbox to have the output signal routed to the chosen output pair (Output 3–4, for example), as well as to the physical outputs (Output 1–2).
When Additional Surround Options is selected in Advanced preferences, the following are available:
Surround Show As pop-up menu: Sets the surround format. The choice you make automatically updates the remaining pop-up menus in the Output pane.
Surround Initialize buttons: Choose between the default setup of Logic Pro, the ITU (International Telecommunications Union) standard, and the WG-4 standard.