Question about JBL PB12 Subwoofer

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Sub freaking out! :-(

My JBL PB12 suddenly started flickering on and off repetitively. Oddly enough, it seems to do it with the bass line. We've never had a problem out of it before - always gotten exceptional bass but now, after 3-4 years, it started this. The lights on the front will flash from green to red and the bass won't make it through. You can trick it by leaving it off for awhile and turning it back on but it will only work for a moment. I have tried changing the power cord, the a/v inputs, all the settings, EVERYTHING but I cannot figure it out. Please help!! :-) Thanks!

Posted by Arienne Wyatt on

  • Arienne Wyatt Jan 19, 2007

    HA!! This is what JBL customer support said (in 2 different e-mails)

    E-mail #1:

    Good afternoon and thank you for your inquiry. I can understand your
    concern. It's possible the power amp may be the issue. Depending on
    the serial number of your sub, it's possible it cannot be repaired.
    Unfortunately, if your serial number begins with "AM" or a number, it
    cannot be serviced. The company that manufactures the amplifier
    assembly's main Power Amp Module is no longer in business. Because of
    this, they are no longer able to supply us with the main part of the
    amplifier assembly. However, if your serial number begins with a "HA"
    it can be serviced. If this is the case, please reply to this email
    with your zip code and I can locate the nearest service center in your

    The serial number is printed on a white label on the back of the
    subwoofer near the ac cord.

    I hope this helps.

    Best Regards,
    Vu Le
    Internet Support Specialist

    E-mail #2 (after I prodded for more information on the exact problem):

    The issue could be the power amp itself. However, it is very hard to
    tell what the actual problem is without physically testing the unit.
    It's possible the issue can also be with a small resistor.

    I hope this helps.

    Best Regards,
    Vu Le
    Internet Support Specialist

    When I called the service center, it's going to be $50 just for them to take it in the door and if it's the amp, which it most likely is, it will be $65/hr labor plus parts. I'm probably going to replace the amp myself (you can order replacements pretty cheap).




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Exactly......I bought a Klipsh

Posted on Oct 31, 2007


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