jazzcrisis
Well-known member
My 24ch. Yamaha PM1000 console is making some very strange noises. Seems to be coming from the master modules...individual channels, auxes, etc are fine. Definitely originating pre-fader, and the unbalanced outputs and monitor outs have the same noise. Phantom power doesn't seem to have any effect, and I don't think the problem lies with any switches, pots, or faders, even though it kind of sounds like a constant scratchy pot noise. It's the same regardless of whether channels are assigned too.
The noise has been here for awhile, though it seems to have become worse after I recapped the power supply. The master modules also have new capacitors.
It's a crackly, whooshing sort of sound that's always there, but it gets better and worse intermittently, over the course of 20-30 seconds usually. It gets better for a few minutes if I turn the console off and back on, so I wonder if it has something to do with capacitors. I think I heard somewhere that bad tantalum caps can make odd noises...
It doesn't sound like a ground issue, but is there supposed to be a separate ground wire (not part of the molex connectors) going to the power supplies? My console didn't have any, but I have seen others that have. If so, where does that connect to? The schematics don't seem to indicate.
I'm attaching a sample of the noise.
Any ideas?
The noise has been here for awhile, though it seems to have become worse after I recapped the power supply. The master modules also have new capacitors.
It's a crackly, whooshing sort of sound that's always there, but it gets better and worse intermittently, over the course of 20-30 seconds usually. It gets better for a few minutes if I turn the console off and back on, so I wonder if it has something to do with capacitors. I think I heard somewhere that bad tantalum caps can make odd noises...
It doesn't sound like a ground issue, but is there supposed to be a separate ground wire (not part of the molex connectors) going to the power supplies? My console didn't have any, but I have seen others that have. If so, where does that connect to? The schematics don't seem to indicate.
I'm attaching a sample of the noise.
Any ideas?