camarada78
Well-known member
I have a Carvin PA620 powered mixer with a weird problem: channel one shuts down the entire speaker output when plugged in. Its not a short because it still outputs sound through the line outs.
1. voltages are somewhat correct (-42/+42, -26, -17/+17, when it should be +-43, -24, +-18).
2. Channel 2 if plugged works normally, no issues, any volume.
3. Channel 1 if plugged very low volume, works normally. if goes a little louder, it shuts down everything (both speaker channels)
4. line out works normally in any situation, even after shutting down.
5. the relays seems alright either but when the channels shut, its after the relays. So something is activating the relays when there is a load present on speaker 1.
6. the problem remains the same with 4 and 8ohm speakers.
I suspected the Zeners (BZX84C9V1) on the -24 rail, but they seem to be ok upon measure.
Any help will be appreciated. Thanks in advance for the help, have a good day.
1. voltages are somewhat correct (-42/+42, -26, -17/+17, when it should be +-43, -24, +-18).
2. Channel 2 if plugged works normally, no issues, any volume.
3. Channel 1 if plugged very low volume, works normally. if goes a little louder, it shuts down everything (both speaker channels)
4. line out works normally in any situation, even after shutting down.
5. the relays seems alright either but when the channels shut, its after the relays. So something is activating the relays when there is a load present on speaker 1.
6. the problem remains the same with 4 and 8ohm speakers.
I suspected the Zeners (BZX84C9V1) on the -24 rail, but they seem to be ok upon measure.
Any help will be appreciated. Thanks in advance for the help, have a good day.
