1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
     
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

QSC PLX 2402 Rattle, Bob Lee steps in.

Discussion in 'Amps and Cabs [BG]' started by JonathanD, Aug 14, 2007.


  1. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    My QSC2402 was rattling as loud as my speakers were playing. very annoying and not acceptable. Not a little rattle, loud rattling.
    I called QSC to get an RA to send back my QSC 2402. I was told that the amp is never suppose to be placed on a speaker cabinet because

    "the fragile components will break from the vibration".

    I said "I better not drive with it in my car then either huh?"(please not sarcasm)
    He said that(paraphrase) "the amp is not designed to be placed on a sub cabinet and to place it elsewhere."

    I said, "so can I send it in for repair or can you tell me how to fix it? I looked on the forum and saw the problem posted but no fix."

    The amp was not made for that application and the fine components will break if you use it in that application"
    I say "whatever, thanks, buy."

    So I say, QSC amps must be for home use only, and don't walk to hard next to them unless you have sturdy floors.

    I place the QSC in a rack with plastic washers, put stuff on it so that it is wedged tight, place it on a p[piece of foam folded over 3 times and 1 carpet sample square and I still get some rattle.
    I can't take that to a gig, its ridiculous.

    Anybody know what I can do to make my precious porcelain amp work without ridiculous amounts of rattling?
     
  2. svtb15

    svtb15

    Mar 22, 2004
    Austin,TX - McKinney,TX - NY,NY, - Nashville,TN
    I play it all. Whatever works for the gig
    I have a Crown Marcotech and it has seen everything short of being dragged behind a truck by a rope.. its still pumping and never a problem.. Sell it and get a crown or a crest:bag:
     
  3. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    How can I sell this to someone? I can't sell something I don't believe works. I will just have to put it on the ground away from my cab, maybe I will put some decorative ceramic pieces on top of my cab instead.
    Jonathan
     
  4. murphy

    murphy

    May 5, 2004
    Toronto, Canada
    I believe it is usually the cardboard thing in the front vent that rattles/ vibrates.
    I thought Bob Lee posted a fix....easy.
    Try to search again.
    I think you can pop off the cover and wedge something to stop the rattle...????

    Good luck
     
  5. svtb15

    svtb15

    Mar 22, 2004
    Austin,TX - McKinney,TX - NY,NY, - Nashville,TN
    I play it all. Whatever works for the gig
    Im sorry .. i was just being a wise guy..

    It most likely something real simple...
    does it sound metallic when it rattles.. Maybe something got sucked into the air vent?
    Have you opened the top to see if anything is floating in there.. I do believe that QSC amps are built upside down so everything is mounted on the upper cover.. so in case something does get in there it stays away from the circuitry..

    I have to agree with what you told that ninny at QSC... The amp will take way more bumping around while in transport than being on top of a bass rig.. i find it scary if it cant take bass rig shaking.. its not like an earthquake!..
    i say take a peek inside and see if anything is simply loose in there.

    I had a piece of gear that the cover rattled LOUDLY.. I took a small piece of weather stripping that you can get at home depot... and i wedged it in there and re-torqued the top screws.. never rattled again
     
  6. Passinwind

    Passinwind I am Passinwind and some of you are not. Supporting Member Commercial User

    Dec 3, 2003
    Columbia River Gorge, WA.
    Owner/Designer &Toaster Tech Passinwind Electronics
    How about doing what Bob Lee told you to in this thread?
     
  7. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Who told you that? Are you sure you spoke to someone at QSC, and not some know-nothing at a dealer or something?

    I assume it's a PLX 2402?
     
  8. Foamy

    Foamy

    Jun 26, 2006
    Sac Area
    Where's Bob Lee? Did he take off kind of, as a result of that stuff a couple months back with regards to folks associated with companies? If so, that totally stinks. He was here for all of us for help with this kind of stuff.
     
  9. rok51

    rok51 Supporting Member

    Sep 2, 2002
    Crawfordville, FL
    Don't look up!
    :p
     
  10. Foamy

    Foamy

    Jun 26, 2006
    Sac Area
    What's that?!! Up in the sky??!!
     
  11. Jeff A

    Jeff A

    Oct 22, 2005
    CT
    Yeah
     
  12. Steve

    Steve

    Aug 10, 2001
    yeah, it's a known issue. It's the air duct rattling against the circuit board inside. An easy fix.

    And who cares if stuff vibrates apart? I had one of the capacitors from the power rail rattle off and still used the amp every night for about six months before I got around to fixing it. (For under ten bucks) The thing never did anything but work and sound good.

    Them are tough puppies!
     
  13. Just FYI, I have 5 PLX3002s in my amp rack for my mains. They have been up to a gig in the mountains that is 65 (SIXTY FIVE) miles of dirt, washboardy road ONE WAY. that makes it 130 miles round trip. They have done this twice and have yet to have one problem with any of them. I want one more of them so I can deligate that rack to monitor duty and am going to be picking up some PL 6.0 IIs for FOH duty. Its alll QSC for me.

    Sorry to hear that you are experiencing this difficulty. Don't give up on them. Not for even one minute.

    Just my .02 worth.
     
  14. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    Does not work. I even took the whole cardboard thing out... did not stop the metallic rattling. I wedged window foam into every spot I could.
    I thought it was the fan assembly, so i tried taping it to the heat sinks and got no better results.
     
  15. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
  16. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    I spoke with a guy with a middle Mideastern-ish accent who was very short at 1800 772 2834. This was after I was transfered to Tech Support.
    And I am sure that is what they said because the repeated it in a slightly different way 3 times.
     
  17. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    Thanks for the help guys, but I already tried the search functions. at this point I have to accept the fact that the amp rattles. It was made 08-04 and I don' have a receipt so I know there will be no more warranty service after this month and I don't have the time to deal with the usual hassle of warranty.

    The Original post was really just me relaying 1 bad experience fueled by a touch of disappointment and shock.

    BTW Bob, any comment on whether the amp should be placed on bass cabs or not?
    Jonathan
     
  18. Passinwind

    Passinwind I am Passinwind and some of you are not. Supporting Member Commercial User

    Dec 3, 2003
    Columbia River Gorge, WA.
    Owner/Designer &Toaster Tech Passinwind Electronics
    Just curious: has the amp always done this, or is it a new development? Also, did you buy it new or used? Are you sure all the mounting hardware is still there?

    Mechanical vibrations can be really frustrating to diagnose and repair. Generally it should be a good bit easier in an amp than in, say, a speaker cab though. Sorry I can't help, save parroting the usual drill here. That's worked well on the two PLXs that I've encountered that had noise issues. FWIW, neither had a lick of problems from then on.
     
  19. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    I think I know who you mean. I'll have a talk with him.

    In the meantime, I recommend that you put the air duct back in the amp. Let me know if you want the amp fixed.
     
  20. JonathanD

    JonathanD

    Dec 13, 2006
    Atlanta, GA
    I do appreciate it passinwind. I bought it used and it has done this since I got it. Unfortunately I didn't get around to using it till 2 months after I bought it.

    Really, I am going to be ok with putting it on the floor so it does not rattle.
    Jonathan
     

Share This Page