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QSC mode equality

Discussion in 'Amps and Cabs [BG]' started by Sanctum, Jan 13, 2003.


  1. Another weekend with too much time to think:

    Currently I run my Eden Navigator into my QSC 1850HD using the stereo outs to each channel of the poweramp (short 1/4" cables.)

    If I only use one output from the Navigator and switch the QSC to parallel input mode, would this still be equal to what I'm doing now as far as output sound? Given I dont change my output setup, which is stereo mode, one output to each cab.

    Just wondering, because even though I'm running in "stereo" mode, I'm not running any stereo effects etc, nor do I bi-amp my rig.

    Mulling.......
     
  2. 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
    That would depend on the Eden Navigator, and I don't have . If the stereo outputs are both the same when you're not using stereo effects, then yes, running with parallel inputs off one preamp output will be the same.
     
  3. Bob,

    Would the S/N ratio be better if using only one preamp channel, with the power amp in parallel?
    ('1x noise' going to the power amp)

    vs.

    Using both preamp outs, with the power amp in stereo ('2x noise' going to the power amp)

    Just curious...

    B
     
  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
    It would probably be identical or very close to identical.

    If the majority of the preamp's noise were in the output circuitry, then the one output => parallel inputs arrangement would probably tend to be quieter.

    But it would be really surprising if that were the case. I would expect the circuitry with the most potential for noise would be the processing--i.e., EQ, effects, et al--and the input stage. I'm guessing that the output sections are mainly buffers, so they shouldn't contribute any significant noise if they're designed right. If the processing is common to both of the outputs (obviously the input is!), then the noise voltage would be the same on each output, and thus the same noise voltage would be going into both amp inputs anyway whether its from one preamp output or both. So there would be no significant difference either way.