A.Yes, this is possible.
The AC-3 provides two different output jacks:
LINE OUT--- for connection to a PA system or a recorder (BOSS BR-series or similar).
G.AMP OUT--- for connection to a guitar amp.
Connect the LINE OUT and G.AMP OUT jacks to your PA system and guitar amp as shown in the diagram.
When you switch the AC-3 on/off, the output will automatically be changed as shown.


(2006/03/27)