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clip

caesard6caesard6 Posts: 7
edited April 2010 in PA General Discussion
Hi, i have a drpa+ and whenever i set it up for 2 way i got no issues but when i hook it up 3 way biamp with my srx 725 and 2 qsc 3602 for the highs, and mids, for some reason my mid amp keeps on cliping. i have tried almost everything possible but yet keeps on cliping. it clips with the amp less than half way. Please help me

Comments

  • GadgetGadget Posts: 4,915
    You will need to go into the xover and see what the gain for each stage is set at... press the xover button and toggle through the H M and L (using the [xover] button, and tell us what the gain is for each crossover..it will be in the lower right corner in each case...

    When you set up the system, did you use a preset, or use the wizard?
    i have tried almost everything possible but yet keeps on cliping.
    That doesn't tell us a whole lot, what have you tried?
    but when i hook it up 3 way biamp with my srx 725 and 2 qsc 3602 for the highs, and mids, for some reason my mid amp keeps on cliping.
    Hmmm this makes very little sense...your running the tops 3 way stereo, and using 2 QSC 3602's... one for the horns, and one for the mids... what about the lows?

    Basically, what I see here is you should be running a 2X5 (mono subs) or 2X6 (stereo subs) that would give you, stereo high's on one amp, stereo lows on the mids and depending on the sub config either a mono or stereo sub setup...I have to hope that you chose the wizard setup, and you chose the 725's and whatever sub...and that then you followed the wizard and did the auto level function? If you don't have the measurement mic and you let that function go that is probably your problem....

    What is the xover gain of the mid amp? from what I see you should probably have to cut the horn gain about 10 db and also use the input volume controls to cut the volume further, if you are indeed using the 3602 for the horns...150-300 watts is plenty for those horns...I would suspect you might have seen this in the wizard correct? ( a BIG cut in the high output and a low gain setting on the amp?)

    All in all, the mid amp sensitivity should have been speced by the wizard did you set it where the wizard said to?

    The xover gain would then be set by the wizard and modified in the level matching... that is where I fear you went wrong...Try setting the High xover gain @ -10, the mid xover @ -0- and the sub I cannot say since you didn't specify anything

    So, in review, the SRX 725 is a bI-ampable cab, yet you specified a 3 way setup so we have to assume subs? You didn't follow protocol here and read the READ ME FIRST BEFORE POSTING section...If you had you would know you need to provide ALL the system inf for a complete answer here. There is also the FAQ section with loads of info...
    viewforum.php?f=60

    JBL provides tunings for their products .... here is the link to the SRX 725:
    http://www.jblpro.com/catalog/general/P ... =117&MId=3
    Just follow the "tunings" link, however if you had followed the setup wizard and had the measurement mic ( I have to assume you do NOT so you skipped that step... and that is where the problem started...) then the system would have had you level matched, crossed properly and with PEQ's and any necessary alignment delay applied for you...

    Don't forget to do "gain structure"...

    Ball is in your court now...
    Gadget
  • caesard6caesard6 Posts: 7
    Hi,
    Here is the crossover settings H (1.18KHZ LR24 -9.0DB), M (90.0HZ LR24 0.0DB) (1.12KHZ LR24) L (40.0HZ LR24 1.2DB) (80.0HZ LR24). Biamp 3way stereo jbl srx 725s and jbl mrx 518s. Amps 2 qsc plx2 3602's for the srx 1 for Hights, and the other for Mids, i have a qsc plx 3002 for the Lows(jbl mrx 518s). Gain on the amps Hights 41%, Mids 41%, I got a custom settings for the Lows 50%. All this settings are from the drpa+. I followed the wizard and used the mic to measure still the amp keeps on clipping.

    Thank you,
  • GadgetGadget Posts: 4,915
    Your back.. and it's been...nearly 6 months... :?

    Well, you still haven't found the problem? Did you do a gain structure? So both mids clip but you never said if they are not loud enough...

    Please give us as much info as you can because we really don't have enough to go on here...

    Info like:
    what kind of cables, did you switch them
    did you switch amps
    what does the system sound like when bi-amped..is it balanced?
    are you using commercially available 4 conductor speaker cables?
    are they wired properly? 1+ and 1- to the lows and 2+ and 2- to the hi's?
    is the switch on the back of the speakers in the bi-amp position?
    when in the bi-amp position does the mid amp affect ONLY the mids, and hi amp ONLY affect the hi's?
    what are the meters on the Driverack doing

    hopefully you won't wait 6 months for your next post..
    Gadget
  • caesard6caesard6 Posts: 7
    Both the hights and mids clip with the sound from the SRX 725s very low. The drpa+ does not clip it's the 2 QSC 3602's that clips below half of the volume. :lol: I have the switch at the back turned down to bi-amp. How do i fix the gain structure please. Do know that all my speaker cables are 1- and 1+ i don't know about 2- and 2+. I buy them from Guitar Center and they are all speakon to speakon. The system seems balanced but i end up getting more mids than the hights. The hights get lost :?:
    In a bi-amp mode the mid amp affects the mid and the hights amp affect the hights :roll:

    Thanks
  • DennisDennis Posts: 801
    caesard6 wrote:
    I have the switch at the back turned down to bi-amp.
    Is that switch at the back of the speaker or the amplifier?
  • GadgetGadget Posts: 4,915
    Ok I think I know whats happening.. you need to get SPECIAL cables to bi-amp.. I bet you have cables that are only 2 conductor.

    unscrew one end of one of the speaker cable (speakon) and see if there are 4 wires in them and all 4 of the terminals are filled, you may even have NL2 connectors with only 2 connections .. that would explain the problem! BE carefull you could blow the amps up doing that!

    to bi-amp you need 2 wires for the mids, (+ and -) and 2 wires for the hi's (+ and -) they all run inside the jacket.. these are expensive to buy and I bet you don't have the right ones...

    What you are doing is feeding the output of the 2 amps into each other...and tha'ts BAD
    Gadget

    Make sure you tell us EXACTLY how you are hooking up the speakers and what cables your using...

    G
  • caesard6caesard6 Posts: 7
    Thank you very much i dont have the 4 wires i only got the 1- and 1+. I am on my way to go get me some new 4 conductor cables and i will keep you posted.

    Thanks.
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