QSC Kinda light in the pants on the higer freqs?

Discussion in 'Amps and Cabs [BG]' started by Mario Lewis, Oct 17, 2001.

  1. Mario Lewis

    Mario Lewis

    Jul 6, 2001
    Clinton, MD
    I've read a couple of reviews on the Bass Gear Review archives that the QSC PLX series of Power Amps is a little light on the reproduction of the higher frequencies, but that it can easily handle tons of lows.

    My current amp is a Stewart World 2.1.

    I'm thinking about selling the Stew and getting a PLX 3402, but one review I read stated specifically that the QSC didn't reproduce the highs as well as the Stewart.

    can anyone out there support these comments? I'd have to sell the Stew, get the QSC and find that I've goofed.
  2. I've read reviews that state the exact opposite. QSC would have great high freq output and lousy bass. It's in the eye of the beholder. Maybe the test was done on a cab with a defective tweeter, maybe they mistook clean'ness with lack of high freqs, maybe the reviewer don't know what he's talking about, maybe the QSCs are indeed bad, maybe they only had 5 minutes to audition the amp, maybe...........

    I'd just go out & play it. SFY, stuff like that.

  3. VicDamone


    Jun 25, 2000
    Joris is right, I've seen conflicting reviews Of QSC products. I bought one anyway, for a 21lb amp it passes alot of volts.

    Compaired to my Pass Labs X350@150lbs the QSC falls short in many sonic areas when used as a Hi-Fi amp. Compairing the two in the bass rig the differences are harder to distinguish.

    I haven't used the Stewart but unless its shutting down from over heating I think you might be spliting hairs between the two.
  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 shouldn't be a problem. They're designed to be solid and clean (ultra-low distortion and noise, no coloration) from 8 Hz up to 50 kHz. The speaker will affect the spectral content of the sound more than the amp will.

    A clean amp might or might not be what you want; a clean amp will simply give you what you put into it, only bigger. If you use your preamp to dial in the sound you want, that's great.

    If you want distortion or other artifacts to get a certain sound and your preamp won't do it, then you want an amp that will add distortion or coloration, such as a tube amp. Distortion doesn't always sound bad; many "hi-fi" amps have relatively high amounts of euphonic distortion that some find adds a certain amount of niceness to the audio signal; the only trouble is that you can't really adjust how much.

    My personal philosophy on power amps is that at that stage I want clean reproduction and no arbitrary additions to the sound. I'd rather have control over EQ and any other alterations, so I use a preamp and effects box for that. Your philosophy may be different.
  5. Nightbass


    May 1, 2001
    Seattle, WA
    Joris is right - you have to take everything you read with a grain of salt (even this post). I doubt if the PLX has any deficiencies in the high end. Some audio purists may fine sonic differences with their hi-fi systems, but that wouldn't be an issue with bass guitar systems.

    Likewise, I've only read reviews about it being weak in the low end, when compared to Crown. But as I posted a while back, the PLX comes from the factory with the 30Hz high-pass filter engaged, while Crowns don't even *have* a filter. So the comparisons are completely invalid.

    All of us who were using the PLX with Acmes thought it sounded better with the 30Hz filter on, btw. The extra LF energy just flapped the woofers around and muddied up the sound.

  6. Maybe the guys who don't like QSC amps were listening to them while hooked up with zip cord wire instead of yuppie wire.. that would explain everything...

  7. Jerry J

    Jerry J Supporting Member

    Mar 27, 2000
    P-town, OR
    I have a PLX2402 and the amp simply scares me. So much power in a light package. I honestly don't find it lacking in any way, tonewise. I replaced my Crown CE1000 with it and have been very happy.

    I agree with VicDamone that you may be splitting hairs. I've heard nothing but good things about the bigger Stewarts.
  8. LowRanger


    Dec 24, 2000
    I use a QSC PLX3002, and agree with Jerry J: tons of power in a light package, and have never been wanting for hi-end response.

    I agree with Bob Lee in terms of wanting my power amp to put out what it's been given with as little coloration as possible. Matched with a Demeter pre, the PLX easily puts out enough high-end to fry both ears and tweeters!
  9. I just got a new PLX 2402, and when it came in I compared it to the World 1.2 I was replacing in my bass rack and the World 2.1 from our PA.

    The QSC sounded at least as good, from the bottom to the top. Frankly, there was not much tonal difference between the three, except that one channel on my World 2.1 sounds duller and weaker but that amp has been beat up a lot.