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power amp comparisons - Crest, Stewart, QSC, etc...

Discussion in 'Amps and Cabs [BG]' started by secretdonkey, Dec 15, 2004.

  1. secretdonkey


    Oct 9, 2002
    Austin, TX
    I will likely be getting a power amp soon, and am only beginning to do my homework. Based largely on impressions I've gotten here at TB, I'll be looking at the following choices of amps in the 1800w bridged at 4 ohm neighborhood:

    Crest CA9
    Stewart World 2.1
    QSC PLX model of similar output
    (other suggestions welcome)

    Quality of sound is my main concern, though if I feel it's pretty close, concerns of weight and value for the dollar will enter into the equation.


  2. NJL


    Apr 12, 2002
    San Antonio
    all i can say is that i have an RMX 1450 and it's heavy....

  3. secretdonkey


    Oct 9, 2002
    Austin, TX
    Some particulars about my setup - I'll be driving a pair of Accugroove Whappo Jr.s and using - initially at least - my SWR SM-900 as a *very heavy* preamp ;) - Since the amp will drive one Junior nicely, I *could* just pair it with a smaller amp to power the other Junior, but going with the larger amp will allow me to migrate to a different preamp without having to change my poweramp setup.
  4. NJL


    Apr 12, 2002
    San Antonio
    you have two accugroove's now?????
  5. DaveB


    Mar 29, 2000
    Toronto Ontario
    I have a QSC RMX850 that I bought as a backup amp for my iamp800. I use have gigged a number of time with the QSC and a Fishman Platinum Bass Pro EQ as a preamp and while it's not the iamp it is a really good rig.
  6. secretdonkey


    Oct 9, 2002
    Austin, TX
    Not yet... ;)
  7. NJL


    Apr 12, 2002
    San Antonio
    how's the cooling on it?
  8. secretdonkey


    Oct 9, 2002
    Austin, TX
    The more I look, the more I like the Stewart. Unless the Crest sounds gobs better, I think it's my top pick at the moment.
  9. NJL


    Apr 12, 2002
    San Antonio
    it would be my pick due to the weight, but i have heard about some thermal issues....but that could be a few isolated issues
  10. NJL


    Apr 12, 2002
    San Antonio
    thanks for clearing that up!

  11. MJ5150

    MJ5150 Terrific Twister

    Apr 12, 2001
    Olympia, WA

    I do not own one, but I jam with another bass player who does. He plays in an aggressive hard rock cover band, and they gig all the time. There has never been a heat issue with his 2.1.

  12. Fuzzbass

    Fuzzbass P5 with overdrive Gold Supporting Member

    Josh nailed it. My additional 2¢: I've been running a 2.1 for three years now. Sometimes I bridge into 4 ohms, sometimes I run one channel into 2.67 ohms. I play in a fairly loud bar bands: in one the guitarist does the SRV thing, in another the guitarist has a Marshall stack. I've played some outdoor gigs with no PA support on hot summer days. Bottom line: I've had no problems.

    I hate to bring up this can of worms, but here goes: some people whose opinions I respect highly assert that heavy "lead sleds" (transformer-based amplifiers) sound better than the lightweight Class H switching amps made by QSC, Stewart and others. I can't comment on this specifically... my ears are extremely pleased with the performance of my Stewart (and some QSC rigs I've tried for that matter), and my bad back will overrule any proposal to take on a lot of extra weight for (perhaps) a slight increase in tone.

  13. secretdonkey


    Oct 9, 2002
    Austin, TX
    Well, thanks for bringing up the can of worms. This is exactly the kind of issue I want to be aware of when I make my decision. I think cost and weight are putting Stewart ahead of the Crest for me at the moment, unless I read something that convinces me the Crest (traditional transformer, iirc) would sound *substantially* better. :)

    Smash, can I take your post as a disagreement (at least based on anecdotes you've read) with Joshua's assertion that thermal problems are only with models without a cooling fan? Are the anecdotes about Stewart in general or the World 2.1 specifically?
  14. lo-freq

    lo-freq aka UFO

    Jan 19, 2003
    DFW, Texas
    Another amp that I've heard a lot of very favorable comments on here at TB is the Crown Macro-Tech MA2402 (another relatively heavy lead sled amp).

    I sure wish I could find some (or some people would perform some) double-blind tests by some respected 'ears' involving all these power amps (plus the Crest Pro 9200, etc. & lab.gruppen fP6400, etc.).
  15. Big String

    Big String Supporting Member

    Apr 22, 2000
    Northwest Indiana
    I don't have that many experiances with power amps as some of the others but here is my take. I've only had one class h switching type power amp and that was a PLX2402. It did a good job for me up to a point. The cabs I am or was using at the time sound way better with extra headroom and or dynamic headroom. The Plx let me down when I needed the extra juice several times on outside gigs. It was a nice amp and was light and well built with nice positive controls and inputs and outputs etc. I liked it even less bridged... it sounded choked to me. I switched to the CA9. It's got the dynamic headroom (I) require to my taste and liking, just so we don't get in a technical debate, because I'm not a technican only a musician. I've never used a Stewart but the two guys (Josh and Fuzz) both use Bergantino cabs like me and have no problem, so I can't say, and I believe they know what they are takling about. So, nothing against any product out there because what didn't work for me works for someone else, and the CA9 is a heavy sucker, but I only use it for the "big gun." I can tell you I've never had to bridge it (not that that's bad, in fact that can be good) I've never come close to clipping it which my PLX did ALL the time even though I had it set correctly. If you get a chance please try some of this gear out, and please crank it up so you don't find out something negative later. Just for the the record I own two QSC MXA (lead sled) amps for over ten years and never had and issue. They are even heavier than my Crest.
  16. Nightbass


    May 1, 2001
    Seattle, WA
    You must have missed the Live Audio Board (LAB) Power Amp Shootout last year. They did exactly that - compared about 50 power amps using double-blind technology. The results are painstakingly posted on the website of a guy named Bink. Google for "Bink" and "LAB power amp shootout".
  17. lo-freq

    lo-freq aka UFO

    Jan 19, 2003
    DFW, Texas
    Thank you very much; I'll check it out. :hyper:
  18. IvanMike

    IvanMike Player Characters fear me... Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    i love my 2.1 and was very happy to get it back today. a few of us had have issues with the 2.1 losing a channel, but the great thing about that amp is the channels are independent so you can still run the other one. The repair of the defective channel took a while, but it was free. Mine is as loud as i need, and for max portability i have it in its own 2 space skb rack. the whole thing is probably 5 lbs heavier than an
    SWR sm-900 :cool:
  19. todd 4ta

    todd 4ta

    Apr 3, 2003
    Here is a link I found to the results

    Amp Shootout Results
  20. inazone


    Apr 20, 2003
    At one time I was using a stew 1.2, plx 1602, plx 3402 and a CA9 depending on the venue. They are all great amps and from what I can tell, they will all last a long time. The plx amps had great features.
    As far as volume, I'll let someone else argue and I dont mean to sound mean but the CA9 kills the others as far as volume. The CA9 is a lot louder than the plx 3402 in bridged mode and doesnt clip. Like Big string, my plx amps clipped a lot. All I can say is try it out for yourself! The difference isnt small. There are mods that can be done to the plx amps but I havent tried that yet. I still own the CA9 and plx 3402.

    btw, I used these amps with berg, epi, accugroove, swr all with 5 string basses.