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Amp makes fizzy noise when passing signal

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by aleclee, Mar 21, 2003.

  1. aleclee

    aleclee TGP Tech Wrangler Staff Member

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    I just got my Soldano Decatone and it makes a fizzy noise when passing signal. I hope you guys can hold off on the fizzy Soldano jokes long enough to hear me out. :)

    Even on the clean channel, the amp makes a hissing/fizzing sound, but only when it's passing signal. When idling (not playing or guitar volume turned down) it's dead quiet. I've tried swapping out preamp tubes and pulling duets but with no joy.

    I'd just as soon not have to ship a brand new amp back to the Manufacturer for service.

    Help (and thanks)!!!
     
  2. prsflame

    prsflame Member

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    I had a very similar problem in My Soldano reverb-O-Sonic. After swapping tubes, etc,and taking it to a tech, the problem ended up being related to a bad input jack on the amp.I never thought the input jack could cause this kind of trouble.Once this was replaced, all was well.

    I'm no amp expert, so hopefully others with more knowledge will chime in.:)
     
  3. aleclee

    aleclee TGP Tech Wrangler Staff Member

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    Thanks for the tip but no joy. I tried using the other speaker jack and running a cable across the FX loop but no joy. I also pulled the chassis but didn't notice anything obviously wrong. :(
     
  4. John Phillips

    John Phillips Member

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    It could be a tube, but more likely something tricky to find - probably a cold solder joint. These can occasionally develop semi-conducting properties and behave like diodes, either causing weird distortion and noises or even picking up radio.

    Does it do it if you plug directly into the FX return? (you may have to preamp the signal with a pedal or something) If so, you know the problem is in the power amp. If not, it's in the preamp.
     
  5. aleclee

    aleclee TGP Tech Wrangler Staff Member

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    Thanks, John. After inspecting the amp, I'm suspecting a cold solder joint as well. :( Looks like this amp is going back to the factory for a looking-at.
     
  6. Adam

    Adam Member

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    The phrase "passing signal" struck me as funny!

    Thanks
    Adam
     
  7. ross

    ross Silver Supporting Member

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    I make a fizzy noise when I'm passing gas.
     
  8. burningyen

    burningyen Vendor

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    I make a fizzy noise when passing judgment.
     

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