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Power amps /ohms/ stereo ??

Discussion in 'Amps and Cabs [BG]' started by afroman, Oct 2, 2002.


  1. afroman

    afroman

    Aug 31, 2000
    Brooklyn, NY
    I currently own a Hartke 3500 with a Peavey 410TVX amd I'm planning on getting a smaller cab.

    Just now I though of maybe getting into the preamp-power amp setup and sell my head and cab, so I can use my SansAmp BDDI as the preamp.

    In terms of power amps, I don't understand the stereo power ratings. For example if I were to buy two Peavey 210TVX (4 ohms each) and a power amp (for example a QSC RMX850) is 300W stereo at 4ohms and 430W stereo at 2 ohms, how much power would each speaker get??? Do I need two cabs to run the amp stereo??
    If I use only one 4 ohm cab, does it mean that the power will be bridged mono at 830W at 4ohms??

    Please help me understand the mono-stereo difference and how ohms play a part in this.

    Thanks....
     
  2. FunkySpoo

    FunkySpoo Supporting Member

    Feb 6, 2002
    In your example above your two 210's would get 300 watts each. Since you're hooking them up in stereo, that is one cab per amp in the RMX850. Yes you need two cabs for stereo. Also yes your one 210 cab will get 830 watts if you bridge the amp. Bridging simply means that the two amps are combining their power. Think of stereo power amps as having two amps in one box, which is what they really are. Hope this helped
     
  3. afroman

    afroman

    Aug 31, 2000
    Brooklyn, NY
    That really cleared everything !

    Thanks for the info...
     
  4. afroman

    afroman

    Aug 31, 2000
    Brooklyn, NY
    If I buy a power amp and run it with ynly one cab, does the amp automaticaly bridge it's power to send it to that one cab.

    I'm thinking of buying a power amp to drive a pair of power hungry 210's, but I'll buy one 210 and the other one will have to wait for a while. I ask this because I'm looking the power amps 4 ohms stereo power rating so that when I have both cabs I can supply the needed power to both (in a stereo setup). But I'm worried that if I plug only one cab, the amp will put out all it's power and could damage the speaker.

    Help me understand.
     
  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
    If you hook up the cabinet to just one channel, no.

    To bridge the amp, you have to specifically set it up that way.
     
  6. FunkySpoo

    FunkySpoo Supporting Member

    Feb 6, 2002
    And it's very simple to do. Even I figured it out.
     
  7. afroman

    afroman

    Aug 31, 2000
    Brooklyn, NY
    Thanks for the answer, you've cleared up my last doubts.