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Two channel amps

Discussion in 'Amps and Cabs [BG]' started by Jeroen, Aug 30, 2005.


  1. Jeroen

    Jeroen

    May 9, 2005
    It seems that there are not a lot of power amps out there that have two separate output channels. I currently have an older EBS EP800 amp which runs 2 x 400 Wats @ 4 Ohm or 1 x 800 Watts @ 8 Ohm bridged. I like the double channel setup since it gives me the possibility to hook up two cabs and play with the volume of the two cabs. This opposed to a one channel amp with daisy chained cabs.

    I believe that Eden has an amp with the same capabilities. Who else makes amps like that? EBS doesn't anymore....
     
  2. well, as far as i know most pwramps are stereo/2 channel typed.
     
  3. wideload

    wideload

    Apr 15, 2004
    I know QSC amps have a parallel mode, which sends one input signal to both channels, that you could then adjust volumes for each cab. As far as individually adjusting tone, that would require 2 preamps, I think.
     
  4. mgmadian

    mgmadian

    Feb 4, 2002
    Austin, TX
    Sounds like you're talking about a normal stereo power amp... in fact, most power amps (QSC, Crown, Crest, Carvin, Stewart, Mackie, etc) are stereo, i.e. have 2 output channels that can be used separately... and it's the rare amp that is "mono-block" (one output channel).
     
  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
    Most power amps not only have two output channels, but also two separate inputs, one for each channel.

    Most of these amps can be rigged with both inputs connected together in parallel, so that one signal can be fed into both amp channels, yet you still have two independent channels; you can use different gains, different loudspeaker loads, et al.

    Most of these amps can be rigged so that the two outputs are mirror images of each other, so when you connect the loudspeaker load across the two outputs, they are in series, which results in double the output voltage of a single channel. This is called bridged mono.
     
  6. Jeroen

    Jeroen

    May 9, 2005
    OK, guys, thanks. Maybe I am mixing up a couple of things. A lot of bass heads are integrated pre- and power amps and those have one output channel, such as SWR, Genz-Benz, Epifani, etc.
     
  7. For integrated heads, the largest Eden (the 800) and the largest SWR (900) are 'stereo' amps. However, I think you are misinformed about this necessarily being a positive when running two cabs... it all comes down to optimizing the cabinet ohms vs. the power amp. For example, if you have two 8ohm cabs and are running the Eden in 'stereo', you are actually putting out very little power per side, since the Eden puts out only a fraction of its power on each side at 8ohms (maybe 250 per side or maybe even less... not sure about the exact wattage here). If you run that Eden bridged (i.e., like a mono amp), and connect both 8ohm cabs, you will be putting out significantly more power into each cab (I believe 1200 watts total, or 600 per cab), since you will now have a total 4ohm load.

    So, in most cases, it's better to either find a 'mono block' amp to run you two cabs (like the EBS650, SWR750, iAmp800, etc., etc.), or to run a 'stereo' head in bridged mode (as long as it can run bridged at the combined ohmage of the two cabs).

    Whew... hope that made sense!

    Edit: If both your cabs are at 4ohms.... you will get full power out of these amps (Eden and SWR) running in stereo.... but you could also get an EBS650 or iAmp800, which can run very safely into a 2ohm combined load and give you all the power you would ever need.