Getting more power from your amp to your sub

Discussion in 'Home Theater Projects' started by Rory Buszka, Jun 18, 2004.

  1. Rory Buszka

    Rory Buszka Supporting Actor

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    This one's for all you PA-amplifier-powered people. I read somewhere that one could get more power from a two-channel amplifier by hooking up the first channel of the amplifier to the first speaker normally, but then invert both the input polarity and output polarity of the second channel so it is operating out of phase with the first one. The result is that there is a lot more current available. Perhaps this could be applied to dual-voice-coil drivers like the Tumult and others for a more powerful, impactful sound that doesn't run out of gas as easily. This only works with certain kinds of amps, that have a separate power supply for the positive and negative voltage. This way, where one supply would be overtaxed at a time and the other would be idling, current is drawn from both power supplies on each inward and outward stroke. I wonder how it would work with dual voice coil drivers driven by the two channels of a PA amp?
     
  2. Rory Buszka

    Rory Buszka Supporting Actor

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    This one's for all you PA-amplifier-powered people. I read somewhere that one could get more power from a two-channel amplifier by hooking up the first channel of the amplifier to the first speaker normally, but then invert both the input polarity and output polarity of the second channel so it is operating out of phase with the first one. The result is that there is a lot more current available. Perhaps this could be applied to dual-voice-coil drivers like the Tumult and others for a more powerful, impactful sound that doesn't run out of gas as easily. This only works with certain kinds of amps, that have a separate power supply for the positive and negative voltage. This way, where one supply would be overtaxed at a time and the other would be idling, current is drawn from both power supplies on each inward and outward stroke. I wonder how it would work with dual voice coil drivers driven by the two channels of a PA amp?
     
  3. Rob Formica

    Rob Formica Stunt Coordinator

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    Sounds like the standard theory of "bridged mono mode". Works with amps designed for it... and remember the minimum resistance of the driver usually doubles (stereo 4ohm = mono 8 ohms) From the QSC FAQ pages:



    Later...
    Rob
     
  4. Rob Formica

    Rob Formica Stunt Coordinator

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    Sounds like the standard theory of "bridged mono mode". Works with amps designed for it... and remember the minimum resistance of the driver usually doubles (stereo 4ohm = mono 8 ohms) From the QSC FAQ pages:



    Later...
    Rob
     
  5. Dave Milne

    Dave Milne Supporting Actor

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    No, Rory's not talking about bridging. He's talking about running sort of, "dual mono, but out of phase within the amplifier" ... if that description makes sense. The idea is that one channel will be draining energy from the positive power supply rail, while the other channel will be draining from the negative rail. Theoretically, this should improve headroom and power output.

    It won't be the same as bridging, but might be a good alternative if the amp isn't bridgeable or if the parallel speaker load would present insufficient load impedance to the bridged amp (very common).

    Now, as to whether this dual-mono configuration would be any better or worse than bridging the amp and driving the speakers in series... I'd have to think about. PA guys can't eaily do this because the in/out jacks on speakers are all set up for parallel connections.
     
  6. Dave Milne

    Dave Milne Supporting Actor

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    No, Rory's not talking about bridging. He's talking about running sort of, "dual mono, but out of phase within the amplifier" ... if that description makes sense. The idea is that one channel will be draining energy from the positive power supply rail, while the other channel will be draining from the negative rail. Theoretically, this should improve headroom and power output.

    It won't be the same as bridging, but might be a good alternative if the amp isn't bridgeable or if the parallel speaker load would present insufficient load impedance to the bridged amp (very common).

    Now, as to whether this dual-mono configuration would be any better or worse than bridging the amp and driving the speakers in series... I'd have to think about. PA guys can't eaily do this because the in/out jacks on speakers are all set up for parallel connections.
     

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