7408 (6v6gt) Crackle on warm up

Discussion in 'Glowing Bottle Tube Amp Forum' started by Mhat, Feb 3, 2016.

  1. Mhat

    Mhat Tele-Meister

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    I bought a pair of 60's GE 7408 tubes for my Princeton Reverb. They sound great with the exception that after the first minute of turning them on, they crackle and pop loudly. After that I can play for 20-30 without issue. They sound great still. Are these tubes in their way out?
     
  2. bparnell57

    bparnell57 Poster Extraordinaire

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    Turn the lights off in the room and watch them. If they look like they're arcing, they're practically useless. Otherwise who knows?
     
  3. BobbyZ

    BobbyZ Doctor of Teleocity

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    You might try cleaning the pins. Assuming the amp didn't do this before it could be dirt or corrosion.
     
  4. ThermionicScott

    ThermionicScott Poster Extraordinaire

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    +1. Clean the pins, consider cleaning and re-tightening the sockets in your amp too.
     
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