Thanks to Bob Lee for the following info but I still have quesitons. He writes: For bridged mono operation, the Speakon connector that plugs into the amp must be wired to pins 1+ and 2+. I have a QSC 2402 going into an Epifani UL410 through a Fatmax speakon cable. I have taken the cable apart and cannot tell how it is wired. I am thinking standard wiring is 1+ and 1-. Should I not run the amp in bridged mode until I figure this out? Any suggestions?