73 twin silverface

Discussion in 'Shock Brother's DIY Amps' started by duffer426, Jul 19, 2019.

  1. duffer426

    duffer426 TDPRI Member

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    have a silverface twin reverb, that when chopsticking the componets I notice when I tap the eyelet/fiberboard the tap can be heard through the speaker. Is this a ground issue? thanks
     
  2. corliss1

    corliss1 Friend of Leo's Platinum Supporter

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    Probably not? Sometimes the boards themselves can become conductive, but it's much more likely you're moving a specific wire a bit, likely in the preamp. I'd try and tap each wire gently to see if you can reproduce it like that.
     
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  3. D'tar

    D'tar Friend of Leo's

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    Cold joints can sound like a snap, crackle, pop;)(or any other arrangement of sounds). I had a Pro reverb that would produce noise through the speaker while tapping the board. Turned out to be a bad joint in the filter housing.
     
  4. robrob

    robrob Poster Extraordinaire Ad Free Member

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    Probably a microphonic component such as a cap is being vibrated when you tap the board.
     
  5. schmee

    schmee Poster Extraordinaire

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    It's not uncommon at all. But can also be an indication of something going bad. Try pre tubes first. If a pre tube is microphonic (very common) it can make much of the board microphonic too when tapped.
     
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  6. BobbyZ

    BobbyZ Doctor of Teleocity

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    Just for fun really check out that resistor that sits inline with the length of the board. That one can get loose when the board warps.
    I'm voting on a bad connection.
    If you haven't already done all the electrolytics, now would be a good time.
     
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