I've got 4 Accusonic/Show amps (2 x PSA-3900, 2 x PSA-31500), all four of them were working in all modes (stereo, bridged, parallel/mono). The following day I was testing them out and all of a sudden all four amps only work in bridged mode but not stereo mode or parallel/mono mode. Has anyone ever seen or heard of this before? I'm testing each one on their own so it shouldn't be a power supply/voltage drop issue. The only thing the four of them had in common is that they were all plugged into the same power bar running through a DBX Driverack PA2. So I tried them individually on a different power bar and a different outlet with a direct signal to each amp, bypassing the PA2 and still have the same issue. What would cause 4 individual amps to all lose stereo mode at the same time? I have verified the following during my trouble shooting:
pics of front and back:
There's probably an obvious reason but I don't know what I'm missing.
Thanks in advance for your help.
- speaker is working: used multiple working speakers with no luck
- Speakon cable is working: wired correctly to pins 1+/1-
- signal is working: balanced signal being sent via XLR
- power supply is working: breaker has been reset
- breakers on all amps are all reset
- clip limit is on but i've tried it off as well with no luck
- 30hz filter is off but i've tried it on as well with no luck
- bridged mode: signal showing on both channels when channel A pot is used, as designed. sound is being sent to bridged output channel.
- stereo mode: Signal is showing on both channels A and B. sound is not being sent to output channels A or B.
- parallel(mono) mode: Signal is showing on channel A as designed. sound is not being sent to output channels A or B.
pics of front and back:
There's probably an obvious reason but I don't know what I'm missing.
Thanks in advance for your help.