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Peavey classic 30, new tubes and PT with absolutely no sound

I have a 12 year old peavey classic 30.PT has been replaced as the old one burnt out and tubes replaced but it makes absolutely no sound. tubes all heat up as they should. but i am not really sure where to start finding out what the problem is.


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  • mitch_mg Nov 13, 2008

    Hi, sorry, i mean power transformer. I have been building tube amps for a year or so but so far i have just built a champ and a 5e3 tweed type amp both of which are simple. this is more complicated for me and on a pcb too but i no about the voltages. It is just a hobby but i would like to try fixing it.. thanks

  • mitch_mg Nov 16, 2008

    Hi Dan
    all sorted, was one of the resistors. Thanks heaps



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I'm not sure what "PT" is , but the heater voltage is separate from the other voltages required for this unit to function properly. Please note that with tube systems, there are voltages in the 300-400V range that can cause injury. If you do not have experience with tube based electronics, I would suggest that you bring this to a service center for repair.

Please update this with what you mean by "PT" and we'll continue from there.


Posted on Nov 13, 2008

  • ABRsvcs Nov 13, 2008

    OK. Since you are familiar with tube systems, look for the high voltage. If not present, the result would be no sound. Check also for any of the resistors that may be open. You should have some in the 470K range and even in the 1-2Meg range. Any of these could be open and preventing proper plate voltages.

    Keep me posted.



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