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Parallel vs bridged modes

Discussion in 'Amps and Cabs [BG]' started by Sanctum, May 25, 2002.


  1. On a poweramp that will run in parallel mode (one input driving both amps), will the power rating be the same as the bi-amp/stereo mode, or is it the same as the bridged mode? I'm betting on the lower of the two, but thought I'd ask. Specifically, I'm looking at QSC's product info but its not clear on this.

    thanks

    greg
     
  2. Richard Lindsey

    Richard Lindsey

    Mar 25, 2000
    Metro NYC
    AFAIK, you can do it both ways with a single input. When you bridge, you can really only use one input anyway. It then becomes about what cabs you need to drive. If it's two to four 4 ohms, you better run your one input into the stereo mode. If you have one 4 ohm cab, you can usually bridge (if your amp can be bridged to 4 ohms).

    This "parallel mode" isn't really a separate operating mode for the amplifier; it's just AFAIK a way of handling the inputs, as if you were plugging your signal into an A-B box set to A and B rather than just A or just B.
     
  3. On a pre-amp that has two "pre-amp out" jacks (such as on the svp-pro) would there be any difference running each out to inputs one and two on a poweramp, rather than just running one out to channel one and running in parallel mode on the poweramp? seems like you'd get the same power either way.

    Greg
     
  4. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    You would get the same power.

    I used my PLX2402 in the bridged mode just one time. While it had head room like you wouldn't believe, I kept feeling it's hot breath on the back of my neck (granted I was on a small stage close to my rig)...but it ran HOT!!!

    The parallel mode allows you to use a single input and give each cab (or group of cabs) their own power amp channel. Works great when using a stack of cabinets of different efficiencies or having cabs on both sides of the stage since each grouping would have its own volume control on the power amp.

    You can also set the limiter and low end filters differently depending on the capabilities of the cabinets.

    Lots of possibilities!!!!

    Have fun!