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Need some help regarding the speaker conectivity

rev1rev1 Posts: 12
edited March 2009 in PA Connectivity
Hello, i need some help setting up a new club sound system, and I've got the dbx pa at my disposal, problem is i cant figure out how to connect it to my particular setup.

The system won't be used for live events, it will be used mainly for dj-ing, therefore the sound should come from mixer>dbx pa>amps.

Here is the complete setup:

4 front speakers, 2x left and 2x right
2 front subs, left and right
2 back speakers, left and right

Front speakers will be powered by 2 amps, subwoofers will be powered by 1 amp and another amp for the back speakers.

-Mihai

Comments

  • DraDra Posts: 3,777
    What is the purpose of the \"back\" speakers in the context of the \"front\" speakers?

    DRA
  • rev1rev1 Posts: 12
    They're purpose is to provide a decent SPL at the back of the room.
  • GadgetGadget Posts: 4,915
    Are they aimed back at the source or are they delay towers? (which the DRPA doesn't have anywhere near enough delay for...
  • rev1rev1 Posts: 12
    They're aimed back at the source, something like a quadrophonic sound setup.
  • DennisDennis Posts: 801
    An overhead diagram with dimensions would be worth a thousand words. Info on your amps and speakers couldn't hurt either.

    Dennis
  • rev1rev1 Posts: 12
    Sure, here are the specs for the stuff:

    Amps:

    3x Install 2000 for the front & back speakers with the following specs :

    Install 2000
    Stereo Power (8Ω) 2 x 350W
    Stereo Power (4Ω) 2 x 560W
    Stereo Power (2Ω) 2 x 720W
    Bridged Mono Power (8Ω) 1120W
    Bridged Mono Power (4Ω) 1440W
    Frequency response 20Hz - 25 kHz
    THD + N 0.05%
    Signal Noice Ratio >100dB
    Damping Factor >300/8Ω
    Input Impedance
    20kΩ (balanced)
    10kΩ (unbalanced)
    Input Sensitivity 0.775Vrms
    Input Connectors Balanced to ground, XLR, TRS
    Output Connectors Speacon + Output binding posts

    1x Install 3000 for the subs, with the following specs:

    Install 3000
    Stereo Power (8Ω) 2 x 700W
    Stereo Power (4Ω) 2 x 1100W
    Stereo Power (2Ω) 2 x 1500W
    Bridged Power (8Ω) 2200W
    Bridged Power (4Ω) 3000W
    Frequency response 20Hz - 25 kHz
    THD + N 0.05%
    Signal Noice Ratio >100dB
    Damping Factor >300/8Ω
    Input Impedance
    20kΩ (balanced)
    10kΩ (unbalanced)
    Input Sensitivity 0.775Vrms
    Input Connectors Balanced to ground, XLR, TRS
    Output Connectors Speacon + Output binding posts

    Front speakers are 15\" woofer,2-way,500W / 8 ohm, full range
    Back Speakers are 12\" woofer,2-way,500W / 8 ohm, full range
    Subs: 2x 1x18\" Subwoofer, 5\" voicecoil 700W RMS

    All components are manufactured by lraudio.fi(in case im missing something and you might wanna check it out), including amps.

    As i am pretty bad at drawing, the distance between the front speakers and the back speakers is ~ 20 meters.

    PS: thanks for the quick replyes, ill try and draw the diagram for the club later today.
  • DennisDennis Posts: 801
    What are the models of the 3 different speaker cabinets. A quick skim of the website did not find them.

    Dennis
  • DraDra Posts: 3,777
    Is it possible to do an outward firing cluster in the center of the room?

    DRA
  • DennisDennis Posts: 801
    The design he is explaining is a variation on the standard club/DJ install configuration of one speaker at each corner of the dance floor aimed at the center of the dance floor. On two of the corners, he has put two speakers for whatever reason. One speaker in each corner might work but 20 meters is quite a spread.

    Dennis
  • rev1rev1 Posts: 12
    Dennis:

    I will be using a bigger version of the Club 12 model, and respectively a smaller version of the fronts, for the back.

    And yes, that is my main setup, i considered that the biggest SPL should come from the front, that's why i opted for a 4 speaker setup and 2 woofers for the front.I was thinking that should be enough for the room.

    Dra, i cannot cluster them, i've thought of that, but the front speakers will be hanging from the ceiling, aimed at the center of the room, as the back speakers.

    So with this explained, do i have any chance of using the dbx pa, or do i need another dsp ?
  • GadgetGadget Posts: 4,915
    Yes... you can use it but if you cover the same area (as in side by side with 2 speakers each side...) you will suffer MAJOR comb filtering, which has LOUD and soft fingers as you walk across the plane of the speakers.. and cancellations and all manner of sonic chaos... a certain amount also from front to back as the speakers coverages merge...

    but... set up a 2x5 or 2x6 setup (stereo)(5 is mono subs) all custom in the wizard and run the front tops off the hi outs the back 12's on the mid outs and the and the subs off the lo outs (mono left for bridged subs)

    Set up the HPF @ 40hz BW18 and LPF @ about 120hz LR24... that's the subs

    Set the HPF for the front and rear speakers @ about 120hz LR24 .. If you can put the subs in the center but together for sure to take advantage of the free 3db coupling.. bridge the sub amp and run he subs parallel...If you splay the front tops to avoid crossing coverage on the ones right next to each other you will suffer far less interaction...

    Gadget
  • DennisDennis Posts: 801
    If this is a DJ system, why should the \"biggest SPL\" come from the front instead of shooting for even coverage?

    If you just must have two speakers per side at the front, you might want to rotate the horns. They are 50*x80* and you might want to rotate them so they are 50* horizontal and 80* vertical although this might create a completely different mess.

    It looks like the install 2000 is underpowered for your set up. How do you plan to wire up all of your speaker/amp combinations?

    You have said the length of your coverage area is 20 meters. What is the width of the coverage area?

    Dennis
  • rev1rev1 Posts: 12
    Thanks for the setup info.

    I will be coupling the front speakers 2 on each side, and i will try to couple the subs in the middle.

    Is there any suggestion for the back speakers ?, i'm well aware of the chaos you're talking about, its exactly how it sounds right now.I thought that the major couse of this was the speakers themselves, which right now are DIY models.

    @Dennis

    Width is ~15 meters.
    The Install 2000 will run in mono, one for each front side, and one for the back, for which i'll get 4x2.5mm2 cables.


    Mihai
  • GadgetGadget Posts: 4,915
    Is this a permanent install? If so, if you can put the 2 horns together that would work best...with wide coverage patterns like 80-90 degrees splaying them to cover 160-180 degrees on both sides you end up with way too much on the walls and covering the center.. and as we said can't really face both forward to cover the same area...or you have the sonic chaos we spoke of...

    Oh and as for the back speakers only run them as loud as needed to meet the sound coming from the front...
    G
  • rev1rev1 Posts: 12
    Yep, its a permanent install, I should get some smaller speakers for the back, good tip.

    Since we're still at it, if you've got some free time, can you check out the website, and make a system that you think should fit great in the room i've mentioned of.

    I'm planning to order the products on Tuesday, so i've still got time to order anything i want.
  • GadgetGadget Posts: 4,915
    Ok perhaps you could get a bit more specific about what speakers you have...what site? What DIY speakers? what room do you speak of?
  • rev1rev1 Posts: 12
    Right now im thinking of ordering a bigger version of the Club 12 speaker, and the Stadium Bass.The room is 20 meters by 15 width.

    Current speaker system is formed from some Dynacords and some no-names.

    Website is www.lraudio.fi.

    Thanks, M.
  • GadgetGadget Posts: 4,915
    Hmmm.. conical horn patterns...I would like to see tighter horn patterns to keep the energy on the people and off the walls and ceiling..especially if your going to put the 2 per side in the front. A 40X 60 with a rotatable horn would be better I would think...like the DAS RS 1264...
    http://translate.google.com/translate?h ... 26hs%3DbZl

    Gadget
  • rev1rev1 Posts: 12
    My front tops have 40x 60 rotatable horn, they're different then what you've probably seen at the Club 12 speaker specs.

    I will couple the fronts 2 by 2 , with one next to each other, left and right.I will also have to tilt them forward so the horn will aim at the center of the dance floor. And i was thinking to use the subs in stereo, so it should go 2x 6 on the DSP.

    One more thing, how high should the horn be from the ear of the listener ?Can i put them as close as i can to the ceiling and just tilt them towards middle ?
  • rev1rev1 Posts: 12
    hi again !

    i've just finished setting up the whole system, but there is a problem,

    i hear only mids from back tops and only highs from front tops.

    i've connected the front to the hi outs
    mids are back
    subs are left/mono

    setup is 2x5 with bi-amp speakers, if i try to use passive it switches to 2x3 and i get no signal on mid outs.


    any suggestions are welcomed.

    Thanks,

    Mihai.
  • GadgetGadget Posts: 4,915
    Yes... you have to go into the crossovers.. you will need to press the crossover button and toggle to the Hi xover and there you will need to find the HPF for the Hi outs and using the encoder, scroll it down to the xover point specified (120hz LR24) it will look kind of like this:

    [ 20hz /-------20khz]

    should look more like this:

    [ 20hz /----------------------------------------------20khz]

    now the slope indicates the LR24 and the line should be solid and meet the slope line but hopefully you get the idea.. I don't have a lot of time right now...

    do the same for the Mid xover...

    G
  • rev1rev1 Posts: 12
    Done, works like a charm.

    Many many thanks for the help ! 8)
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