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John Heath John Heath is offline
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Default Peavey Classic 60 questions

On Tuesday, January 12, 2016 at 9:51:45 PM UTC-5, Trevor Wilson wrote:
I have one of the above-mentioned amps on the bench. Pretty
straightforward - 3 X EL84 output valves have air inside the valve. The
plate on one valve appears to have suffered somewhat, but I don't expect
any serious problems apart from that. However, my main questions a

* Should I match the output valves (more accurately, buy a matched quad
from Evatco)? Cost = AUS$100.00/set. Tung-Sol, Genalex (I have an
aversion to Chinese valves, even though they are cheaper),
Electro-Harmonix, JJ, etc.
* My other supplier has no matched sets (and I don't want to buy a
crap-load so I can match them), but sells two brands: Sovtek $13.75 each
or Electro-Harmonix $17.05.

Although cost is not an over-riding concern, the time to ship the Evatco
valves could be. My other supplier can ship today.

Thoughts appreciated. Particularly from PA.

--
Trevor Wilson
www.rageaudio.com.au

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The plate on one valve appears to have suffered somewhat !!

Here is the schematic

http://www.blueguitar.org/new/schem/peavey/c30schem.gif

You could have a leaky grid capacitor C32 or C35 .0022 uf at 400 volts if the plate appears to be over heated. They are cheap so just change them both.. Also tube amps are still popular so a music sort with a repair shop will usually have a tube tester. He can match up the output tubes for gain , emission and check if gassy. If you feel uncomfortable repairing this amp a local tech in a music store can do all this for you. Do not go to the TV repair man. He is qualified but it is unlikely he will have a tube tester. You want the repair tech in a music store as he will have a tube tester and has been there done that many times and will know how to match output tubes and change coupling condensers if necessary.