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Biamp setup Q's with speakon

albuht813albuht813 Posts: 4
edited July 2008 in PA Connectivity
So I've been searching around for 2hours but could not find threads to my application... Learned a heck of a lot, but here goes.

Speaker: (2) JBL SRX 728S

Amp: (2) QSC RMX 4050HD

The above are my mid/high speakers and amps I'm currently using. I have a sub as well, but this question just concerns the biamp setup. From my research, I now know that I need a 4 conductor speakon cable to plug into the back of the speaker. However, the QSC amplifier's only will allow a 4 conductor speakon output from one channel. THe other channel is a +1/-1 output.

So with 4 XLR outputs from the driverack PA, and 2 outputs of 4 conductor speakon...how do I get a stereo biamp setup? If I am not able to get a stereo biamp configuration, what options do I have to still get a biamp setup?

Thanks in advance!!

Comments

  • albuht813albuht813 Posts: 4
    To further clarify my question, I'm also wondering how the mid and high L/R outputs should connect to the 2 amps. From the quick 3 way setup, I'm very confused. Hopefully the drawing below will help explain. My problem is that with 2 XLR inputs, I only have one 4 conductor speakon out and I don't know which speaker it should go to?

    From the quick setup guide, it seems to be telling me this??

    L mid -> mid amp -> which speaker?? (I only have one 4 conductor speakon output
    R mid ->

    L high -> high amp -> 4 conn. speakon (same issue)
    R high ->

    OR........should it be this way?

    Lmid -> amp #1 -> speakon out to L speaker
    Lhigh ->

    R mid -> amp #2 -> speakon out to R
    R high ->


    Please help me sort this out. THanks.
  • Fanman20Fanman20 Posts: 223
    Question

    Isn't the JBL SRX 728S a sub???

    http://www.jblpro.com/srx700/728S.htm

    What are the top boxes??

    Mark
  • Fanman20Fanman20 Posts: 223
    edited July 2008
    However, the QSC amplifier's only will allow a 4 conductor speakon output from one channel. THe other channel is a +1/-1 output.

    The 4 conductors are
    2 conductors from the left amp (Ch 1) +1 and -1
    and
    2 conductors from the right amp (Ch 2) +2 and -2



    An assumtion I will make is that the top boxes are bi -amp boxes and that they have a \"bi -amp speakon connector\" on them

    If this is true than your second option will work

    Driverack out L mid -> amp #1 Left -> speakon out to L speaker \"mids\" LF (+1 and -1)
    Driverack out L high -> amp #1 Right -> speakon out to L speaker\" Highs\" HF (+2 and -2)


    Driverack out R mid -> amp #2 Left -> speakon out to R speaker \"mids\" LF (+1 and -1)
    Driverack out R high -> amp #2 Right -> speakon out to R speaker\" Highs\" HF (+2 and -2)

    (post corrected to aviod confusion)


    The speaker cable out of amp must be 4 wire (speakon conectors) going to speakers

    Read page 6 of your amp manual http://media.qscaudio.com/pdfs/manuals/ ... N_revF.pdf
    Use CH 1 speakon (which has Ch 1 and Ch 2 conected to it)

    (More info on top boxes is needed)

    Mark

    PS read this link

    http://www.jblpro.com/srx700/BiAmp.htm

    and http://www.jblpro.com/srx700/PDF/SRX700%20UserGuide.pdf
    page 8
  • DraDra Posts: 3,777
    Bi-amping requires 2 amp channels (1 whole amp). The \"A/1\" channel input and the \"B/2\" channel input are outputted (for safety and convenience) from output \"B/2\". Channel \"A/1\" output is still active, but paralleled (at all times) to \"B/2\" pins +2/-2.

    DRA
  • GadgetGadget Posts: 4,915
    All wonderful and good...but very confusing to this old sound man...

    Here:
    http://media.qscaudio.com/pdfs/manuals/ ... N_revF.pdf

    It clearly shows on page 6 of the 4050 manual, that Speakon jack 1 is a 4 pole jack... AND if you send the LF info to input #1 that it then sends the 1+/- info out to the SRX on those pins and that in fact....the SRX 700 will then have LF info @ the speaker...(page 8 SRX manual)

    http://www.jblpro.com/srx700/PDF/SRX700%20UserGuide.pdf

    further if you send the HF info to the #2 input (4050), it will rout the HF info to pins 2+/- of speakon connector #1.

    With a Speakon 4 cable the SRX will then get the HF info from pins 2+/- and \"ta da...\" one side all ready for inputs from the driverack.

    Gadget

    I guess I just had to do that for my own edification....
  • Fanman20Fanman20 Posts: 223
    Isn't that what I said???

    Mark
  • Fanman20Fanman20 Posts: 223
    Arr
    slight error (Should read)


    Driverack out L mid -> amp #1 Left -> speakon out to L speaker \"mids\" LF (+1 and -1)
    Driverack out L high -> amp #1 Right -> speakon out to L speaker\" Highs\" HF (+2 and -2)


    Driverack out R mid -> amp #2 Left -> speakon out to R speaker \"mids\" LF (+1 and -1)
    Driverack out R high -> amp #2 Right -> speakon out to R speaker\" Highs\" HF (+2 and -2)

    That better???

    (The old cut and past failure)
  • albuht813albuht813 Posts: 4
    Fanman20 wrote:
    Arr
    slight error (Should read)


    Driverack out L mid -> amp #1 Left -> speakon out to L speaker "mids" LF (+1 and -1)
    Driverack out L high -> amp #1 Right -> speakon out to L speaker" Highs" HF (+2 and -2)


    Driverack out R mid -> amp #2 Left -> speakon out to R speaker "mids" LF (+1 and -1)
    Driverack out R high -> amp #2 Right -> speakon out to R speaker" Highs" HF (+2 and -2)

    That better???

    (The old cut and past failure)


    Thank you all so much!!! I understand and I will be looking into some 4 conductor speakon to hook this thing up!!

    And yes, the 728 is a typo...it's supposed to be the 725.
    Thanks again!
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