Scratchy noise when powering amp head on/off...any advice?

[tele-nova]

I have a tube amp head that when i power it on or off it sometimes makes a low, static rumbling noise very briefly. The sounds last about 5 seconds or so and then the amp plays perfectly fine. It almost sounds like a vinyl record being scratched under the needle. The amp is 11-12 years old and has never been serviced.

I have replaced pre and power tubes yet the issue seems to persist. I know the pots are dirty and produce a static sound when I turn them. Could that play a roll? Maybe a dirty input jack? And why does it only happen sometimes?

I'm no tech so I don't feel comfortable fiddling around inside to try and diagnose the issue so I was hoping someone here with more knowledge than myself might be able to give me some idea what's going on.

 

[MuddyWolf]

It's nothing forget it.

 

[JustABluesGuy]

If your pots are scratchy they need to be cleaned. It may not fix this issue, but will help prevent future problems.

It might also need some caps and such replaced. If you don’t feel comfortable going inside the amp yourself I would recommend taking it to a good tech to clean the pots and check the capacitors and such.

Good luck with it!

 

[schmee]

What amp? It may need a cap job by now, especially if it's a modern amp.

 

[tele-nova]

What amp? It may need a cap job by now, especially if it's a modern amp.

Ampeg gvt 15h

 

[tele-nova]

Also, should I avoid using the amp until a tech has seen it?

Like I said it functions normally otherwise.

 

[Skydog1010]

Also, should I avoid using the amp until a tech has seen it?

Like I said it functions normally otherwise.

I would continue to use it.

 

[printer2]

Use it. I had an amp do the same thing, just do not recall which or what I did with it. A leaky coupling cap?