Peavey 30 Classic Tweed- valves question (1 Viewer)

[therealjohnny]

Is thre anywhere in town I get get replacements?

When I hold a note a grating, vibrating sound comes from the back of the amp so I'm guessing a valve is going

Is it an easy job to change them?

 

[PaoloJM]

Is thre anywhere in town I get get replacements?

When I hold a note a grating, vibrating sound comes from the back of the amp so I'm guessing a valve is going

Is it an easy job to change them?

If it is a power valve then you'll a set of 4 x EL84s. They are fairly common valves so any decent store should be stocking them. You'd probably get a better selection and pricing on-line though. I prefer JJ/Tesla EL84s if you're looking for recommendations. If it's the peamp valve then you'll need three ECC83 (12AX7) valves.
The Classic looks to be fixed bias but it doesn't seem to have an adjustable trim-pot so it looks like you can just remove the old set and put the new set in their place. It as easy a job as changing four light bulbs, just make sure to line the pins up correctly as you'll bend them trying to shove the valve in the wrong way. EL84s are "keyed" by leaving one free pin space on the valve and a corrosponding space in the valve socket.
The ECC83s definitley don't need to be biased and they are "keyed" in a similar fashion to the EL84.
Are you sure it's not something other than the valves though. They don't normally making a vibrating noise when they're going that I know of, it's usually more of a fizzing, crackly noise? Preamp valves can squeel like hell if they're microhponic but nothing that would fit the vibrating description? If it's more of a ocillating sound like a the "putting" of a two stroke engine then it's more likely to be a faulty capacitor.

 

[therealjohnny]

thanks for that

I have no idea really how it works

I'm not sure how to describe it-i just know theres something not right..


You might be right about the capacitor but I really couldnt say


Might be best to drop it into a shop or someone with the knowhow to fix it?