Stumper.....What do YOU think it is?

[Stratophile]

I have a Peavey Classic 50. Lately, but not always, when I am playing at louder volumes the sound starts to cut out and back on. It's not the cables. It's something in the amp.

It won't be a complete loss of sound but a huge drop in volume and then it might come back and be fine or it might just be back and forth real quick like.

What do you think the issue is? I have new power tubes in it.....could it be a pre-amp tube? A cap? Cold soder somewhere?

It might do it for a few days then not do ti for months and then rear it's ugly head again! It's driving me crazy and that's a short trip!:D

[rockon1]

Could be a lot of things as far as bad connections go. Try the simple stuff first-check the connections to the speakers. A COMMON simple cause is bad contacts in the FX loop jacks-if your model has a loop AND your not using it that is. If so an easy way to check is to use a patch or guitar cable and plug it into the loop. If the problem goes away the jacks need servicing. Also could be bad contact on your tubes sockets. You can simple spray the pins with contact cleaner and slide each tube in and out of the sockets a few times to get better connection sometimes. Thats all I got.....Bob

[Stratophile]

Thanks I appreciate your time.

I do use the effect loop. so that might not be it....but it maybe still could. I suppose it's possible I funked up the jacks at some point breaking down teh gear.

I have contact cleaner so that will job one here in a minute!

would you say it's more likely to be POWER tubes or pre tubes or all the above?

[Stratophile]

Bump...big negative on this one. I changed the inverter tube thinking that might be a culprit.

Contact cleaner.....cleaned the amp up really nice.


Still it does it. Volume takes a big nose dive and then drifts back in and out.

[Wakarusa]

The PV classic 50s I've had on my bench have suffered from bad control pots (cheap Alpha stuff that won't take much abuse -- like dropping something on top of the amp -- and will start to go intermittent) to bad/cold solder joints.

The first trick is to see if your problem is caused by vibration since you say it happens when you play louder. Try running the amp into an external cab and see if it still misbehaves. If it does, I'd look for a bad pot or a bad tube, and lastly for a component (like a resistor) that fails when it gets hot. If it behaves thru the external cab look for a bad/cold solder joint, bad pot, or a broken/weak component lead.

[Stratophile]

Cool beans. I'll try that. Thanks.

How much do you think it would cost to have a guy go through the amp if I can't find it?

[Wakarusa]

How much do you think it would cost to have a guy go through the amp if I can't find it?

I have no idea what your local tech would charge nor how long he/she/it might take.

If you walked into my shop with it I'd quote an hour, see if I could figure out what's gone loopy within that hour and then call you back to discuss how far you wanted to go with things. It's really difficult to quote this kind of problem. It may become instantly clear what's wrong when your tech cracks it open, or may take painstaking hours to track down.