CR120 noise on dirty channel

[arstacey]

Hello everyone. I just picked up a CR120 head in a trade. The clean channel works perfectly but when I switch to the dirty channel I get a LOT of noise. Humming, hissing, crackling. You can hear the guitar but at a much lower volume than the noise. Has anyone experienced this and/or point me in the right direction to get it working properly?

[liaztraht]

Haven't experienced it with my CR, but had a similar issue with an old bass amp.

Have you looked at the circuit board yet? In my bass amp there was a busted volume pot. I would first check for any physical damage to the dirt channel pots and the traces on the PCB.

[arstacey]

I have not checked it out yet. Going to do that this weekend. Hoping it's an easy or at least obvious fix.

[liaztraht]

They do have some odd looking pots in them. I did have some issues with a scratchy gain pot that bound up a little bit. There was a pice of metal in it that looked like the nub you have to trim off of most pots. Could also cause issues with the contacts if that's your case.

The pots are open backed. So it is easy for dirt to get in them. If there is no damage some electrical contact cleaner might work if its just dirty.

[Les Paul Lover]

I have not checked it out yet. Going to do that this weekend. Hoping it's an easy or at least obvious fix.

Be careful.
Working on amps isn't recommended unless you know what you're doing.

You may be better off bringing it to a tech - safer, and the diagnosis may be better/faster!!!

[arstacey]

That's what I've decided to do. We have a local Orange authorized repair center. Bench charge is $80 and hour though and they are backlogged a month. I'm a little hesitant though as I can get a used one for $300. Hoping the problem is not that bad.