Amp popping when stand-by switch is engaged

Discussion in 'Amps and Cabs' started by James, Sep 15, 2008.

  1. James

    James Member

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    Hello,

    My amp is making a popping noise whenever I engage or disengage the stand-by switch. What are the common causes of this? It used to be dead-quiet when the stand-by switch was used.

    Thanks,

    James
     
  2. sdgvintage

    sdgvintage Member

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    is it a tube rectifier amp?

    I have seen certain rectifiers do that. Swapping in a different rectifier fixed it.
     
  3. 3 Mile Stone

    3 Mile Stone Silver Supporting Member

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    Bumping for more info. I have heard this on occasion and it has concerned me too.
     
  4. FrankieSixxxgun

    FrankieSixxxgun Member

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    It's too early for me to remember the exact name of the caps in the amp, not the filter caps, but that usually means they're bad. It's not a big deal, but if you replace 'em you'll get rid of the pop. Mine pops too, but I just don't care enough to fix it.
     
  5. Structo

    Structo Member

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    I think it is caused by where the switch is placed in the circuit.
    If it is before the caps or after the first cap in the filter.
     
  6. James

    James Member

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    Thanks for your replies, mates! Yes, it's a tube amp (Allen Old Flame) with a tube rectifier.
     
  7. ChickenLover

    ChickenLover Member

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    In just about every case the Standby switch is rated for 125v or maybe 250v and in guitar amps it is used to switch the B+ which is often ~450v. Very often all that it needed is a .01uF/1000v cap across the SB switch...some builders add them as a matter of course.
     

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