A frog in my JBL SW?

Discussion in 'Speakers' started by Wendell Miles, Jun 22, 2004.

  1. Wendell Miles

    Wendell Miles Auditioning

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    Over the last several weeks I have noticed that my SW makes a "croaking" type sound when it first powers up. It only happens once and will not happen again until I turn it back on again. Other than this sound anomoly occurring during startup, no other problems that I can tell. Anyone know what might cause this and if so, is it a significant sign of an upcoming SW failure? Thanks.

    JBL PB12 -- approximately 18 months old.
     
  2. Wendell Miles

    Wendell Miles Auditioning

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    Over the last several weeks I have noticed that my SW makes a "croaking" type sound when it first powers up. It only happens once and will not happen again until I turn it back on again. Other than this sound anomoly occurring during startup, no other problems that I can tell. Anyone know what might cause this and if so, is it a significant sign of an upcoming SW failure? Thanks.

    JBL PB12 -- approximately 18 months old.
     
  3. John F. Palacio

    John F. Palacio Supporting Actor

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    Wendell Miles says:

    Most subwoofer amps have a muting circuit that blocks the output from reaching the driver for the second or so while the power amp is turning on and therefore muting any noises.

    It appears, in your case, that this circuit has failed. Hard to predict if this means that other items on the amp are going south or not.

    My advise would be that if it is still under warranty, have it fixed. If not let it go and see what happens.

    Good luck!
     
  4. John F. Palacio

    John F. Palacio Supporting Actor

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    Wendell Miles says:

    Most subwoofer amps have a muting circuit that blocks the output from reaching the driver for the second or so while the power amp is turning on and therefore muting any noises.

    It appears, in your case, that this circuit has failed. Hard to predict if this means that other items on the amp are going south or not.

    My advise would be that if it is still under warranty, have it fixed. If not let it go and see what happens.

    Good luck!
     
  5. Fred_Krampits

    Fred_Krampits Stunt Coordinator

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    My JBL E250P sub makes a noise when it powers up too, it's done that since it was new. I don't think it's a sound played through the speaker, I suspect it is something like the piston engaging.

    It's so slight though, I really am not bothered.
     
  6. Fred_Krampits

    Fred_Krampits Stunt Coordinator

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    My JBL E250P sub makes a noise when it powers up too, it's done that since it was new. I don't think it's a sound played through the speaker, I suspect it is something like the piston engaging.

    It's so slight though, I really am not bothered.
     

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