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PEQ adjustments for cabinet arrays

DraDra Posts: 3,777
I'm looking for tips and techniques when arrying cabinets. I just added a pair of top cabinets. I sold my Peavey Impulse 200's and bought a 2nd pair of Yorkville E12's (used passive). These cabs have an 80H x 50V horn that can be rotated to be 50H x 80V. The \"trap.\" included angle is of the cab is 16 - 20 degrees, as near as I can tell. A butted side wall array looks really nice, but that leaves a very large over-lap even at 50 degrees. A straight ahead approach yields an almost dead over lap (good for volume, but nothing gained in widening the field).

I do not want to get into a situation of switching back and forth, but I would consider having a pair of each if that would be an advantage. Most (80%) set-ups are for DJ'ing with cabs set up 10 - 20 feet apart. Live sound gig's are usually conventions and school or church related functions with stacks up to 80 feet apart. The rooms are sometimes 2 or 3:1 long or 2 or 3:1 wide. Speakers are typically on stands and usually with the horn 2 feet or so above ear level when standing.

1. Are there any rules of thumb that apply here? Which angle combo is best for a given situation?

2. In the case where the cabs are all firing ahead, should the horn frequencies be attenuated with a hi-shelf filter? If so, again, is there a good rule. I will auto EQ outside, but what should I expect?

3. Any answers to questios that I didn't ask, but are helpful are also appreciated.


Thanks,
Dra

PS - Sounds like a good time for an \"Arraying 101\".

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    kpippenkpippen Posts: 551
    edited June 2007
    Dra wrote:
    These cabs have an 80H x 50V horn that can be rotated to be 50H x 80V. The "trap." included angle is of the cab is 16 - 20 degrees, as near as I can tell. A butted side wall array looks really nice, but that leaves a very large over-lap even at 50 degrees. A straight ahead approach yields an almost dead over lap (good for volume, but nothing gained in widening the field).
    Simple...even I know the answer to this one!... Put the horns in either top cab on the reverse diagonal from each other... You'll have 65D (opposed to 80H X 50V)...plus you'll gain six ddBs...:)
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    DraDra Posts: 3,777
    You ever have one of those days, that nothing seems to make sense? This must be one of those days, because I don't understand any of what you are trying to say. Opposing cabinet? 6db?

    Please expound.

    Dra
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    kpippenkpippen Posts: 551
    Having a serious day?...:shock:
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    wolfgongwolfgong Posts: 74
    Dra -

    I'm way behind on this post. Could you post a picture for my smallish visually oriented processor?

    W
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    i think he means rotate the horns halfway, but in opposite directions from each other...
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    kpippenkpippen Posts: 551
    kpippen wrote:
    Put the horns in either top cab on the reverse diagonal from each other... You'll have 65D (opposed to 80H X 50V)...plus you'll gain six ddBs...:)
    Golly geeze guys,

    1. 65D = 65 degrees of diagonal dispersement...
    2. ddbs = diagonal decibels...

    It was suppossed to be funny...:lol::lol::lol::lol::lol:
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    DraDra Posts: 3,777
    Oh... ha ha.

    Kevin you gotta set up the punch line.

    Wolfie, if you think you're behind, check out Kevin's idea.

    To get the flying V like Kevin suggests, I'll just lean the cabs together like a Tee-Pee and shoot a drywall screw in to hold them secure. For venues that only require 1 cab per side I'll use a 2x4 painted black as to not attract attention. Then all I have to do is make sure that the chairs are placed in diagonal lines.

    Dra
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    GadgetGadget Posts: 4,915
    Hey Wolfie...

    Not a lot of time tonight but here's a quickie...

    The 80 Horizontal would be usable in single cabs per side.
    Flip them to 50 horizontal for arrays with 100 degree coverage per side. Cabs right together...

    shoot I have to go.. I'll get back as soon as I can..
    G
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    kpippenkpippen Posts: 551
    Dra wrote:
    To get the flying V like Kevin suggests, I'll just lean the cabs together like a Tee-Pee and shoot a drywall screw in to hold them secure. For venues that only require 1 cab per side I'll use a 2x4 painted black as to not attract attention. Then all I have to do is make sure that the chairs are placed in diagonal lines.
    And the chair legs on the diagonal inside should be cut down so the audiance is sonically synced-up with the array...
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    DraDra Posts: 3,777
    That's a good start Gadget. But too much is never enough. Keep it coming master Obiwon.

    Dra
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    wolfgongwolfgong Posts: 74
    OK, I got the Gadget explanation.

    Separately, I need to fly a JBL JRX118S.

    Got any ideas on keeping this thing from falling on my head.

    Hmmm... that last part of the phrase sounds familiar. Something Dra said about headroom, me thinks.

    Cheers!

    W
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    DraDra Posts: 3,777
    The safest way would be to disassemble the cab (take out the speaker), drill holes as close to size (I'd say 3/8\") for 3/8\" eyebolt. Use fender washers (extra large OD available for sure at Lowe's) for bigger foot print on the wood inside and out so you can \"clamp\" the cab to avoid \"stretching\" the hole when it hangs. I would use bolts with enough thread length to \"double nut\" the inside. Use \"blue\" thread locker if you need to remove in the future, \"red\" if not. (you have to heat with a torch to remove and not a good idea in a wood enclosure.) Set the amount of hold pressure with the first nut then add the jam nut and put the mojo on it and the first. Don't forget the thread locker.
    If you go with the perforated U channel use the same fender washer techique.

    Dra
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    kpippenkpippen Posts: 551
    edited June 2007
    Dra wrote:
    The safest way would be to disassemble the cab (take out the speaker), drill holes as close to size (I'd say 3/8") for 3/8" eyebolt. Use fender washers (extra large OD available for sure at Lowe's) for bigger foot print on the wood inside and out so you can "clamp" the cab to avoid "stretching" the hole when it hangs. I would use bolts with enough thread length to "double nut" the inside. Use "blue" thread locker if you need to remove in the future, "red" if not. (you have to heat with a torch to remove and not a good idea in a wood enclosure.) Set the amount of hold pressure with the first nut then add the jam nut and put the mojo on it and the first. Don't forget the thread locker.
    The flying JRX115i I installed also show some support on the bottom side of the cabinets... It appears that JBL probably uses 3/8-16 all-thread rod that goes all the way through the cabs with a wide diameter flush-mount threaded cap on the bottom end... So I would use Dra's procedure but with all-thread rod through the cabinets and also put 3/8 x 2" fender washers on the bottom side with double locking nuts (a nylon lock thread type for the second nut or maybe an acorn nut with lock-tite for that finished look)... The unistrut method might be easier and probably wouldn't look so obtrusive if painted flat black...2cents.gif

    Disclaimer: I Kevin Pippen makes no representations or warranties regarding the afore mentioned mounting procedure or its suitability for use. By using the afore mentioned mounting procedure in full or in part the installer assumes liabilities and risks associated with the use or misuse of this procedure, including any harm or damage to equipment and/or facilitiy or persons that have access to it. I Kevin Pippen shall not in any event be liable for any direct, indirect, punitive, special, incidental, or consequential damages, including, without limitation, lost revenues, lost profits, or lost headroom arising out of or in any way connected with the use or misuse of the afore mentioned mounting procedure.
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    DraDra Posts: 3,777
    Alright! Back to my original post. Is this correct? Multiple top cabs horns in a stack should over lap horizontally as little as possible, if at all. Left and right cabs stack's horns should overlap as much as possible to the opposite stack. But at the same time avoiding spraying the stage.
    Input?

    Dra

    PS - It appears as though if I put the wedge bottom of one cab flush to the trap side of the other cab is is incredibly close to a perfect array with the 50 deg rotation. There will be a\"cavity\" but no through gap. Apparently Yorville thought that out.

    I was going to insert a pic / drawing, how do I do that?

    [/img]
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    kpippenkpippen Posts: 551
    Dra,...email it to me and I'll hook you up...

    Kevin
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    DraDra Posts: 3,777
    Thanks kevin.

    This is what I was describing in my last post. Is this ideal or too much in?
    If this works I may just rotate all of the 50 degrees and leave them.

    e12dispersion.gif

    Dra[/img]
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    GadgetGadget Posts: 4,915
    I'm back

    Ok if you were going to (not germain to this post but if you were wondering) for 4 per side horns @ 80 horizontal, all 4 horns together, so there would be woofers below, and above the horns, all cabs tight together. For another row above or below woofers together.. horns above... so it would be woofer-horn-horn-woofer-woofer-horn...vertically, with rows on either side the same configuration. When having left right stacks its more important to keep the information on the audience and off the reflective surfaces than it is to be concerned with coverage overlaps... if you can accomplish both .. great. It's often impractical to have front fills so the hanging L/R's need to cover the front centers also.. but a center isle offers some ability to manage comb filtering. In multiple speaker array's there is a procedure called power shading where the speakers that are closer to the audience are set to lower volumes and these that have to project to the farther regions are long-throw and run louder...You can steer groups of subs with delays also (they have to be together though). Information on these and other techniques are searchable in a \"google search\" using keywords.. including programs like EV's \"Array show \" which is a freeware program. There are also programs that offer coverage prediction and even speaker types/mfg's models that would best suit the application.

    As Kevin said, through bolts are necessary, but the corners also usually have internal metal angle bracing at least on the sides. two hangers and a swing bolt should suffice. 'T' nuts on the bottom should suffice with a pinch bolt that would also hold the metal angle in the corners.

    anything else?
    Gadget
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    kpippenkpippen Posts: 551
    Dra,

    Your horn dispersion is almost identical to the four flying JRX115s I installed... They are exactly the same distance between and toed-in at almost the same angle... What I did is working-out very well...

    Looks great to me; but you have to consider......

    Kevin
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    wolfgongwolfgong Posts: 74
    Dra -

    I really like the picture. My head has stopped spinning for now.

    : )
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    GadgetGadget Posts: 4,915
    Yup,
    You got it! good use of the techniques and information... more important to keep the sound off the walls and on the people.

    G
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