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QSC RMX (1450) info wanted!

Discussion in 'Amps and Cabs [BG]' started by jock, Dec 3, 2001.


  1. jock

    jock

    Jun 7, 2000
    Stockholm, Sweden
    lso, whats the difference between class AB and H Output Circuitry? (The 1450 is AB) How does that affect the sound?
     
  2. jock

    jock

    Jun 7, 2000
    Stockholm, Sweden
    The first part of the thread got deleted...Here it is:
    I found a used QSC RMX 1450 at a good price. How does it sound and is it reliable? How does it compare to the PLX series?
    Also, whats the difference between class AB and H Output Circuitry? (The 1450 is AB) How does that affect the sound?
     
  3. On my site under the QSC tab, there is a PDF called Anatomy of an Amplifier. This will teach you a lot.

    The RMX-1450 is a nice amp. Reliable, $413 average selling price on eBay. It weighs 40 pounds. It is made off shore to QSC specs. I had the RMX-850 and it was built like a tank.
     
  4. 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
    Class H is Class AB but with more than one set of supply rail voltages. In most Class H amps there are two sets--high and low--while very high-powered amps might have three or even four. Most of the time, the signal can be handled by the low-voltage rails, but on peaks, the high-voltage rails kick in to allow the signal to be reproduced cleanly.

    This arrangement boosts efficiency because a power amp is more efficient the closer to maximum power it operates. Having two sets of supply rails and switching circuitry to switch in the higher rails when needed is essentially like having two maximum power levels in the same amp.