My amp changes channels on its own at high volumes??

[Dale23219]

I bought a used Dual Rectifier over a year ago. Sometimes when I have it pretty loud and the footswitch is in use it will literally change channels on its own. If I unplug the footswitch it stops changing channels on its own. I'm pretty certain it can't be the footswitch though because i ordered a new footswitch and cable a while back and I still have the same problem. I have asked a few other people I know with Mesas and none of them have any clue what it could be. If anybody has any ideas I would love to hear them, it's a really big problem when playing live.

 

[YellowJacket]

2 or 3 channel Recto? Is it the cable. A short in the cable can cause it to change channels on its own.

Otherwise, take it to a tech.

 

[thunda1216]

maybe a bad opto-thingy?

 

[94Tremoverb]

If it happens with the footswitch plugged in but not without, and it's not the footswitch or the cable because you've tried different ones, then it's a faulty footswitch jack on the amp. There's nothing else that's not in the circuit when the footswitch is unplugged.

It could just be dirty or needing re-tensioned. Most like the spring contact is not making a good contact with the plug tip, or the inside of the barrel is corroded. Either of these could be vibration-sensitive.

 

[JW123]

Stop diming the bass! that will fix it

 

[Third Age Amps]

It's either an intermittent short in the switching circuitry: a wire that has a cold solder joint or a loose wire. Or one or both of the switching relays is sticking. Remove the chassis and lightly tap on the relays 10-15 times with the end of a screwdriver. Re-install and try it then. If that doesn't fix it, you'll have to send it in or take it to a reliable tech.

Word of warning though, intermittent problems can take a LONG time to troubleshoot so it can be a little costly.

 

[Dale23219]

Well I finally took the amp to have it looked at, and I am waiting to hear back. He says that he doesn't see it being a hard fix so I'm hoping that's the case.