Hum in Power Amp

Discussion in 'AV Receivers' started by Louisp, Jan 18, 2005.

  1. Louisp

    Louisp Stunt Coordinator

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    What can cause a low level hum from speakers connected to an additional power amp?
     
  2. Elinor

    Elinor Supporting Actor

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    Bad caps in the amp.

    Ground loop anywhere in the system.

    Power cord parallel to speaker wire/amp interconnect.
     
  3. John Garcia

    John Garcia Executive Producer

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    Ground loop would be the first thing to check for. Start with your CATV/SAT cable connection. If that's not it, then I'd disconnect and reconnect each source to see if any of them stop the humming.
     
  4. Kevin. W

    Kevin. W Screenwriter

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    If your ear has to be right next to the speaker too hear, its probably just the amps transformer.

    Kevin
     
  5. alan halvorson

    alan halvorson Cinematographer

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    Try plugging everything into one outlet. This eliminates differences in potential.
     
  6. John Garcia

    John Garcia Executive Producer

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    I had everything plugged into one outlet (via a Panamax 5100) and I still had ground loop hum from my CATV, so that is not always the case.
     
  7. JohnSmith

    JohnSmith Supporting Actor

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    What about humming from the amp itself? I have one amp that hums.
     
  8. Wayne A. Pflughaupt

    Moderator

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    Alan was talking about a ground loop that can be caused when the gear is plugged into circuits on opposite phases.

    Regards,
    Wayne A. Pflughaupt
     
  9. Chu Gai

    Chu Gai Lead Actor

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    Can you make out the tune?
     
  10. Karl_Luph

    Karl_Luph Supporting Actor

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    I have a pro audiostereo soundcraftsman amp that has a hum(actually ,more of a buzz) in one of the channels. A signal can get amplified through it,but it's distorted with the buzz that gets louder as you turn the amp up. I figured it may be bad caps too. The other channel is great.
     
  11. Elinor

    Elinor Supporting Actor

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    Yeah, my main 3-channel amp buzzes/hums for the first 5 minutes of warmup. I'm figuring new caps are in its near future.
     
  12. Louisp

    Louisp Stunt Coordinator

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    Pardon my ignorance but what are "caps"?
     
  13. JeremyErwin

    JeremyErwin Producer

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    Capacitors
     
  14. Louisp

    Louisp Stunt Coordinator

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    Thanks
     

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