Does this sound like a microphonic tube problem?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by WienerDog, Jul 4, 2008.

  1. WienerDog

    WienerDog Supporting Member

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    My amp's distortion channel sometimes makes a "whoooooo" noise. The noise goes away if I unplug the guitar cord from the amp's input jack. The noise also goes away if I power down and power up again.

    What could this be?
     
  2. slider313

    slider313 Silver Supporting Member

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    The only way to tell if it's a preamp tube is to change one at a time and see if the noise goes away.
     
  3. alivegy

    alivegy Member

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    It can still be a preamp issue. But when my preamp tube had gone microphonic i could tap the chasis of the amp with my finger and hear the tapping through the speaker.
     
  4. 12guitdown

    12guitdown Member

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    Same here. Just knock on it, like your knocking on a door. You'll know really quick whether it's a tube or not.
     
  5. mattwasserman

    mattwasserman Member

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    Wiener Dog
    I am having the same problem with my amp, did you figure out what the problem was with yours. If so how did you fix it?
    Thanks.
     
  6. Blue Strat

    Blue Strat Member

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    If the problem only occurs with the guitar plugged in, it's probably something external to the amp.
     

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