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Speakon wiring question

Discussion in 'Amps and Cabs [BG]' started by GrooveMonkey, Jun 30, 2004.


  1. I have a speakon equipped speaker cable that's configured for bridged mono on my QSC power amp. Can I use tha same cable for single channel stereo use without re-wiring it?

    The reason I'm asking is that I forgot all about it being specifically wired for mono and I switched my power amp into stereo mode and it still worked fine...

    Is there any harm in leaving it this way? :meh:
     
  2. HeavyDuty

    HeavyDuty Supporting Curmudgeon Staff Member Gold Supporting Member

    Jun 26, 2000
    Suburban Chicago, IL
    Not enough info. Is it wired straight through (+1 = +1, etc.) or is it wired specially?

    In any case, changing the pinout of Speakons is quite easy.
     
  3. Thanks Heavy.

    The cable is configured +1 +2 per the QSC RMX mono requirements.

    [​IMG]
     
  4. Thunderfunk

    Thunderfunk

    Mar 27, 2004
    McHenry, IL
    Normal Speakon wiring is +1/-1 for left channel, and +2/-2 for right channel. Bridged is +1/+2. BUT, when you go to bridged mode, one of the channels has it's phase reversed. This is done with an inverter (usually opamp) in the signal right before one of the channels, and is why there's a stereo/bridged switch. If this wasn't done, both +1 and +2 would be pushing in phase, and the only output would be any difference between the two channels, which would happen if you used a stereo effect that created difference between the channel signals.

    There might also be a mono switch, which would combine the two channel preamp signals without inversion of one of them. The only thing that makes sense with what you said is the bridged switch remained in the bridged mode, even though you switched from mono to stereo. I'm not familar with your amp, so I don't what the switching options are.

    There's another thing that might become obvious. Since in bridged mode you're using two hot signals you have to be careful that the speaker signal doesn't get grounded outside the amp. That would damage the amp.

    Dave Funk
     
  5. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    It would be wise to either re-wire it, or even better, get yourself an additional cable wired the way you need.
     

  6. Thanks Bob, thanks everyone.

    It looks like I'll be picking up a new speakon cable tonight....
     
  7. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Be sure to label which one's which. ;)
     
  8. modflea

    modflea

    Apr 26, 2004
    Lafayette, LA
    Oh crap!

    I just bought a Monster Speakon cable for my Ampeg SVT810. I'm running my amp in bridge mode. So you're saying I have to get the cable modified? Do I have to get both ends modified?
     
  9. Just the power amp end needs to 'pin' to the right connectors. There's a +1 -1 +2 -2 stamped on the inside of the speakon connector. Depending on your power amp's requirements for which connectors pair up for which mode.

    Chances are you've just been using half of your amps power all this time...