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QSC PLX 3002

Discussion in 'Amps and Cabs [BG]' started by bizzaro, Nov 3, 2001.


  1. bizzaro

    bizzaro

    Aug 21, 2000
    Vermont
    TOO MUCH POWER??

    Ok you tech wizards out there--Would this be overkill. I am tired of having all of my equipment maxed out and distorted, and still not able to hear myself. I was in a loud Classic Rock band and am now in a Country Rock band. It will be just as loud. Can you have too much power? I am sure in order to get the equipment to perform you have to be driving it to some degree. I will be pushing a pair of 12's @400 watts RMS each and a 15 that is 600 watts RMS.
     
  2. BigBohn

    BigBohn

    Sep 29, 2001
    WPB, Florida
    you can never have too much reserve power in your poweramp. In my rig, i run 2 SWR Goliaths, a total of 1400W RMS, and I use a Carvin DCM2000 to power em, which does 2000W @4 Ohms RMS. Essentially, you don't want to run your power at full capicity. There is a general rule of thumb that says you should have a poweramp that have a maximum RMS of 2-3 times that of what your total cabinets can handle RMS. EX. a 1x12(2 of them, together at a total of 800W RMS) and a 1x15(600W RMS) will equal a total of 1400W RMS at whatever ohms the cabs are. Please specify them. So, basically you can't overpower them, just don't raise them past the RMS level the cabs can take, and they won't blow. If you want anything more detailed, just ask, I'll make it clearer.
     
  3. No.

    :D
     
  4. bizzaro

    bizzaro

    Aug 21, 2000
    Vermont
    Thanks !!
    And now the follow up questions......
    Currently the 12's are at 4 ohms but I will put them in series (16 ohms)when I get the 15 cab put together. The 15 is 8 ohms. The 12's have an spl rating of 100, While the 15 is down to 93. Not a great match but that is what I have. I am hoping that running the 15 at 8 ohms and the 12's at 16 ohms will help even out the power (volume) output. Is it unwise to run the channels at different ohm's? Potenial damage? The QSC PLX 3002 is currently in the dream stages only, and I will need a preamp. Any suggestions? I do own a Rocktron Basix Bass Preamp. Would this be a flagrant missmatch? The preamp is older (early 90's).
    :confused:
     
  5. BigBohn

    BigBohn

    Sep 29, 2001
    WPB, Florida
    cant help ya about the SPL, but a good preamp to check out would be:

    Super hi-fi:
    Eden Navigator

    Clean hi-fi w/ tube grit:
    SWR Interstellar Overdrive

    Full on clean, tube grit:
    Ampeg SVP-PRO
    or
    the stereo Ampeg SVP-BSP

    all great preamps, just play em and find a sound you like.
     
  6. bizzaro

    bizzaro

    Aug 21, 2000
    Vermont
    Any preamps with biamp built in??
     
  7. SONICATTACK

    SONICATTACK

    Sep 26, 2001
    in the sun
    sounds like you need a X-over. Are you planning to run your rig biamp'd? realize that the more ohms the less power sent to the speaker. I would suddjest to wire them so that the amp see's them the same. i.e. 8 - 8 rather than 16 - 8. Make up for the SPL irregularities on the input level of the amp. The PLX amp's are awsome! My band just bought (2) 3402's, days of power and clean! you can't even tell that they're on. Also I don't see a problem in having two differn't ohm loads on one amp, being that each channel have nothing to do with eachother, exept the power supply.

    By the way I'm planning to buy a 1602 for my rig which will be (2)10's and an 18" cab.:D
     
  8. No.

    The 3002 is only about 275 watts per channel at 16 ohms. Will that be enough for your 4-12" drivers?

    If you leave them at 4 ohms you can deliver 900 watts to them.

    I prefer running in stereo mode with my PLX2402, without a crossover. You can adjust tone and volume separately for the different speakers, and I prefer the sound to biamping.

    I currently run a Trace 18 and a Bergantino 115, and in a small setting use mostly the 15 and increase the 18 as needed. If I really need loud, I can switch the cable to one with a speakon wired 1+ & 2+ for bridge mono.

    Aloha,

    Jonathan
     
  9. bizzaro

    bizzaro

    Aug 21, 2000
    Vermont
    It is two 8 ohm 12's, not four, so I have to go 4 or 16 ohms for the twelves. I did consider putting a horn in with the 15 when I build it so I can get it down to 4 ohms and have a horn pull up my highs?This is all hypothetical as the QSC is what I hope to get but can't afford right now. So Johnathan your running just one side of your amp quite often. I was wondering if it is advisable as that is what I will do when I get the 15 built. Use just the 15 for smaller venues and practice. Then add the other cab,(12's) when I need it. And sonic I guess your right it makes more sense to adjust the volume at the amp rather than try and adjust the ohms to compenstate for the db level. I will have more power to draw on if I need it.
     
  10. Alembic F-1X
    Aguilar DB680 (bi-amping with the National Debt :D)
    Eden WP-100
    Maybe others

    I have the F-1X and still use a Rane MX22 active crossover because it has superior performance than any built in crossover.