Discussion in 'Amps and Cabs [BG]' started by product 14, Jan 10, 2004.

  1. Qsc plx 3402

    13 vote(s)
  2. Crown K2

    3 vote(s)
  3. Other Amp

    3 vote(s)
  4. Power Amps are un'pure and they really suck. If you pick this??????

    1 vote(s)
Multiple votes are allowed.
  1. What would you get a Qsc plx3402 $1199 or a crown K2 $1499 the K2 has a damping factor of >3000

    the crown has 1,600watts bridged at 8 ohms 2,500 watts at 4 ohms bridged

    Qsc has 2,200watts, and 3,400watts respectivly with a damping factor of >500
  2. In a recent thread on this very topic Bob Lee from QSC posted:

    My choice was QSC. I spent some time researching and bought a PLX3002 for myself so there's a slight bias here. Also, I recall some issues with the K2 model during the HK transition.
  3. their has been a very similar thread about these amps and I know it was very informative for me. Do a search for crown and qsc. You should find something.
  4. Passinwind

    Passinwind I Know Nothing Supporting Member


    Edit: I own two PLXs (1602, 2402) and a K2. They are all fine amps, and which one I use depends on the feature set I need for a particular gig.

    Both lines had some issues at one time or another, and both manufacturers will take care of those amps if you happen upon one. The price difference quoted above doesn't really reflect the used market, where either one can be had for about the same money. Take a look here: http://www.prepal.com/manufacturers.htm

    --Charlie Escher
  5. inazone


    Apr 20, 2003
    Call lord valve for a better price on the qsc.
  6. g4string

    g4string Supporting Member

    Sep 19, 2002
    Melissa, TX
    I not trying to high-jack your thread, but someone please tell me if this is true. Does speaker resistance affect dampning factors.

    I just purchased a new PA. The guy who sold me the PA was telling me to run my subs paralell at 8 ohms each instead of bridged-mono at 4 ohms. Supposedly, this will affetct the dampning factor and inturn produce a more punchy bass resoponse. ***, is this true?
  7. If the amps are close to the subs, then why would you allow such a lack of headroom/power???
  8. Yep. Damping is defined BY impedance.

    Here's why he said what he did: When you bridge an amp, you add the two sides in series with each other. What this does is roughly halve your damping, BUT with just about any modern amp, it's still going to be more than enough and you won't be able to tell much of an audible difference if at all aside from volume.

    Let me put it this way: if the amp is so crappy that you can hear a major difference in punch between bridging and stereo, it's probably junk. The power you will 'lose' to stereo will have a far greater affect in terms of volume loss than damping will have tonally.
  9. billys73


    Apr 25, 2003
    Crest CA 9. Do they still make this series of amps?
    I liked it better than the Crowns or QSC's.
  10. notanaggie

    notanaggie Guest

    Sep 30, 2003
    To add to what PBG said (with which I agree), there probably isn't an amp made with a bad enough damping factor to screw up the sound.

    Figure it out....

    A damping factor of 1000 means the amp output impedance is around 0.004 ohm if compared to a 4 ohm speaker.

    That 4 ohm speaker probably has an internal resistance of around 2.5 ohms. The speaker wire adds a little more.

    All the resistance in the circuit affects damping, including the speaker and wire resistances.

    Do you really think the sound will be better if the total is 2.504 ohms instead of 2.508 ohms?

    Naw, if the damping is at least 50, I defy anyone to find a difference between that and 500. If you hear something, it will be due to other amplifier characteristics, like power supply, etc.

    I like QSC, to me they sound more open than Crown. And I think they also have a bit more punch.
    The Crown K2 sounded just a little dull and "Peaveyish" to me.

    Gee, lets see, QSC has more power and cost less.....sounds maybe better....thats a tough one!

    But I doubt you could go far wrong with either one.
  11. Sufenta

    Sufenta Trudging The Happy Road of Destiny

    Mar 14, 2002
    The Signpost Up Ahead.
  12. g4string

    g4string Supporting Member

    Sep 19, 2002
    Melissa, TX
    I am using a PLX-2404 to power two Bag End S18E-C sub woofers. So, I am not using a crappy amp or driving crappy speakers.

    Basically, you guys are saying that there should not be an audiable difference in the response of my sub-woofer system when powered 4 ohm bridged-vs-8 ohm parrallel?
  13. Phat Ham

    Phat Ham

    Feb 13, 2000
    If it were my money I would go for the QSC. I've only had good luck with QSC amps, and only bad luck with Crowns. It's hard to explain, but most the Crowns I've dealt with (powerbase2, CE1000, XLS402) just didn't sound right to me. Like they had a wierd midrange or something. I've also seen them all fail at one time or another. I've even seen a macrotech go down when I was at a show. I've never used a K2 though, so they might sound better.

    QSC amps, on the other hand, sound better to me and I've never seen one go down.
  14. Passinwind

    Passinwind I Know Nothing Supporting Member

    I am using a PLX-2404 to power two Bag End S18E-C sub woofers. So, I am not using a crappy amp or driving crappy speakers. Basically, you guys are saying that there should not be an audiable difference in the response of my sub-woofer system when powered 4 ohm bridged-vs-8 ohm parrallel?

    Nobody's said that, AFAIK. In bridged 4, each cab sees 1200 watts. In parallel 8, each sees 425 watts. That's what you're going to hear the difference from, not damping factor.
  15. Passinwind

    Passinwind I Know Nothing Supporting Member

    I like QSC, to me they sound more open than Crown. And I think they also have a bit more punch.

    I have to say , I haven't used my K2 much for bass (I use it for PA usually), and I'd never A/B'ed it and my two PLXs. So I just did that, for a few hours. Strictly subjective, I didn't level match rigorously or any of that stuff. I tried two different preamps, and 4 speaker cabs total. I was initially surprised by how different the 2402 and the K2 sounded. Then I turned off the limiters and filters on the PLX. Things got really similar at this point, especially when I got into level matching a bit more carefully. My conclusion was that I should put a limiter and HPF on the K2. I've always run it that way for PA, no surprise that I should for bass too.:cool:
  16. I like QSC and Crown equally. They both make great gear, and the old K2 issue I mentioned earlier is past history. Like everyone else who's been around for a while I've schlepped my share of DC300A amps around, and one must respect the mighty Macrotech. When it came to the crunch though, I chose QSC for my personal bass rig. The primary reason was because of Bob Lee, reliability and all the standard things you'll see listed in this thread. But there was another "historical" reason I did not choose Crown that, although slightly "off topic", should provide some light amusement. I know Bob Lee will enjoy this one.

    When I was younger I had saved my pennies for a serious stereo system and chose a Crown IC-150 for the preamp and DC-150 for power. It wasn't cheap for a young guy like me (back then), but the day finally came when I had enough scratch to buy it. I remember unboxing the system, drooling all over the included B&K response graphs and hooking it up to find... one channel dead. Quick checklist... not the cables, not the power amp etc. Arrrgh. Quick rush back to the store before closing. The service tech was kind enough to put it straight away up on the bench. What we found inside was that the harness for one channel was not hooked up and actually had never been connected or soldered. Problem solved in short order. Marched it home, hooked it up, sounded great.

    But that brings me back to that lovely, detailed, colour B&K graph. The measurements could NEVER have been made on the preamp I had received, although the printout was very specific about the serial number. Did they pump these things out by the hundreds and just fill in the serial number when boxing 'em up? It was pure BS. From that point on, Crown was a company that I never fully trusted.
  17. If you've already got a PLX2402, there's NO point in getting a bigger amp. That 400 watt rating for the Bag Ends is no joke and more power will only overstress your speakers. With the ELF/Infra system, 400 watts is it, since the crossover is already making the speakers do some SERIOUS excursion, much moreso than a conventional subwoofer. They're not as forgiving as "normal" speakers. If you need more volume, you need more speakers, not more power. Get another pair of S18E cabs and run them in stereo off the amp you have now.

    I strongly recommend AGAINST running even your current amp bridged through those speakers, much less a more powerful one. I have heard a pair of D18E's run off of only 200 watts each that could still make you crap yourself.
  18. VicDamone


    Jun 25, 2000
  19. g4string

    g4string Supporting Member

    Sep 19, 2002
    Melissa, TX

    I never said I needed more power! I was told that running them at 8 ohms would produce more punch and a tighter repsonse due to the dampning factor at 8 ohms-vs-4 ohms. I have thought about runing them at 8 ohms parallel-vs-4 ohms bridged. I will try this and see how it sounds. Thanks for the heads-up about Bag End speakers not be "forgiving". I will take heed.

    Is that how you spell heed?
  20. Passinwind

    Passinwind I Know Nothing Supporting Member

    Could you be specific regarding issues with QSC?

    Sure. The early run of PLX amps had a well documented problem with bad ribbon cables. Here's a link:


    The fifth post down that thread has Bob Lee's description of the problem. Bob's a great asset, here and elsewhere. I don't know if any Crownies are lurking here, but there are some good ones from that camp on some other net forums I frequent. Crown has always treated me well, and been very efficient, when I've dealt with them, as well.

    I purchased a 2402PLX from the same dealer and compared (using my stereo system) the one working channel of the K2 to an single channel of the 2402. In my subjective opinion the differences were overwhelmingly in favor of the QSC. To be honest, these differences may not be all that apparent in a low-fi bass rig.

    I mentioned that I could hear a pretty obvious difference in my bass rigs, but it'll be a few days before I can follow up and do a proper test. I don't want to tip my hand, but each amp had strong points and weak points, IMO. Neither one sounds as good as my Hafler P-3000 to me, but that amp is way too small for most people to gig with. Anyway, until I fire 'em up with my drummer, I'm not passing judgement in public.

    --Charlie Escher