Amp Diagnosis Help

[yyz2112]

I bought an old (1992) amp which has developed an issue. I am getting a white noise/rf type of hiss on all 3 channels. It does not increase with gain, but does increase when the master is turned up. The overall volume has decreased as well. The tubes are good and glowing, those are not the issue. I'm thinking caps, as they are still original.
Thoughts?

 

[jackthehack]

Might help if you gave us the make/model of the amp and more details?

 

[yyz2112]

True enough. Peavey Ultra 60 head, 4 12ax7a and 2 6L6GC, 60 watts.

 

[Superlizard]

:icon_scratch:

Old crusty dried out power caps or perhaps even the power t00bs.  Something in the power amp section says I.

 

[yyz2112]

:icon_scratch:

Old crusty dried out power caps or perhaps even the power t00bs.  Something in the power amp section says I.

I agree, and I tend to think caps, beacuse I did a check with a new set of tubes, and the problem is the same.

 

[jimh]

:icon_scratch:

Old crusty dried out power caps or perhaps even the power t00bs.  Something in the power amp section says I.

+1.  Bad caps in teh power supply, and/or poor earthing.

 

[yyz2112]

I'm hoping it is just the filter caps, a relatively cheap and easy fix-for a tech, I'm not screwing with HV.
I had a more scary thought though. Is there any chance that the OT is going bad?