Amp squeals uncontrollably

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by CBeeper, Oct 4, 2006.

  1. CBeeper

    CBeeper Supporting Member

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    Maybe someone can help me with this. When I try to run my amps in a stereo rig for some reason one of them starts to squeal as soon as you take it off stand-by. I've been running two amps for years but this one particular amp seems to not like the idea. If I unplug the second amp she's fine. What cause's this? Grounding issues? I run the amps through my pedalboard with a Gig-fx Chopper splitting the signal at the end of the chain.Every other amp I've run through this set up has worked before.
     
  2. Blue Strat

    Blue Strat Member

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    Wierd! Have you tried the amp individually again just to be sure it doesn't have a problem?
     
  3. CBeeper

    CBeeper Supporting Member

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    Yes. It works fine. I went nuts for a week. I re-tubed it. Changed out the preamp tubes multiple times. Poked around inside to see if any of the leads had become loose. Nothing. I would have the amp on the bench and it would play fine. As soon a s I put it together and plugged it in the set up it would ring and squeal. I finally realized it was the stereo set up when I unplugged the other amp. I was just going to try the other wire to see if the lead was bad and the noise stopped dead.
     
  4. Blue Strat

    Blue Strat Member

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    What happens when you connect the amps to the splitting device with no other connections going into the splitting device?
     
  5. CBeeper

    CBeeper Supporting Member

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    I haven't tried that yet. I'll give it a go this evening.
     
  6. trdlasvegas

    trdlasvegas Member

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    To see if it's a grounding issue use a AC ground lift on one amp. If it goes away it's a grounding problem with that new amp your trying to use.

    I had this happen with a Crate SS amp. Never solved it but it was definatly a grounding issue inside the Crate amp.

    -Tony
     
  7. CBeeper

    CBeeper Supporting Member

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    Good suggestion. I'll give it another go tonight and see if I can isolate the problem.
     
  8. brad347

    brad347 Member

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    There's only one possible answer:

    it's a ghost.
     
  9. CBeeper

    CBeeper Supporting Member

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    :crazy :AOK
     
  10. CBeeper

    CBeeper Supporting Member

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    Bingo! It was a grounding issue. Lifted the ground on one of the amps a the squeal is gone. You learn something new every day.
     
  11. rockon1

    rockon1 Member

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    Is that safe?
     
  12. brad347

    brad347 Member

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    if the amps are both running on the same rig then I think only one needs to be grounded. Wouldn't swear to that though.
     
  13. CBeeper

    CBeeper Supporting Member

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    I'll check with the manufacturer on the grounding issue. Something isn't right in any event since this is the first in about 12 amps I've owned that has done this.
     

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