Sudden hum sound from tube amp

Discussion in 'Amp Tech Center' started by Jiriho, Oct 8, 2018.

  1. Jiriho

    Jiriho TDPRI Member

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    I recently bought a brand new VOX AC4TV full tube amplifier 3 days ago. Since then the amp has been working great, however, today I hooked up a Joyo overdrive pedal to it, when I unplugged the pedal and I plugged in the guitar directly to the amp, there is a loud and constant humming sound coming from the amp, which becomes almost unbearable if I turn the volume knob past 12 o'clock. This happens with or without any pedals connected. I also haven't changed the location of the amp to where it was previously, and there is nothing around it that would cause interference. Also, when I unplug the guitar the hum continues with some crackling.

    Now I'm wondering if the particular pedal that I plugged in has damaged the amp in some way, though I don't see how this could have happened. Does anyone know what might be wrong.

    Appreciate any comments or help!

    Thanks
     
  2. BobbyZ

    BobbyZ Doctor of Teleocity

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    Best bet on a 3 day old amp, take it back.
    It could just be a bad tube, yeah I know it's new, that doesn't mean anything really.
    It could be something like a bad solder joint or burnt resister.
    Could be you bring it back into the store and it works fine.

    Although you might try reseating the tubes, pull um out and put um back in, one by one. Might even see one that's slipped out a little right off the bat.
    But really since it's new, let them sort it out.
     
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  3. Strato50

    Strato50 Tele-Afflicted

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    I'm thinking bad tube...but in today's mass product produced world I would return it...could be a lemon.
     
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  4. Uncle Daddy

    Uncle Daddy Tele-Afflicted

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    Jack socket contact stuck open.
     
  5. Jiriho

    Jiriho TDPRI Member

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    Thanks, appreciate the comments. Yeah I think best bet is to take it back to the store. Cheers!
     
    BobbyZ likes this.
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