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Crossover recommendations

csantoscsantos Posts: 5
edited January 2007 in PA Configuration Wizard
I'm looking for crossover recommendations for my system. I'm not a sound tech, but i'm learning and any help would be great, I'm booked for this New Years and I would love to maximize the power of my system.

This Is what I have:

Mackie 1604 VLZ Pro
Crown Powertech 2.1
Crown CE4000
DriveRack PA
2 EV T52+ speakers ---> Powertech 2.1 (I know i'm underpower the speakers, I will be replacing this amp with the CE4000 and then get another amp 800W at 8ohms for my subs latter)
2 EV T18 Subs ----> CE4000

The link to the T52+ specs is http://www.eviaudio.co.jp/download/ev/t52plus.pdf

The link to the T18 specs is
http://192.112.63.14/Electrovoice3/file ... 18-eds.pdf

I don't understand how to setup the crossover for these speakers. Also If someone could also help me with the Gain structure for the MACKIE mixer. So far what I understand about the Gain Structure for this Mixer is to bring down the faders for the main and the chanels connect a cd player to individual channel L/R and PAN the chanels L/R according to the input. Solo the chanel and use the PFL mode and start the pink noise cd and start bringing the trim/gain up until it starts cliping on the main LED and back off just enough until the cliping disapears, and then do the same for the other chanel. My question is, is this the right way to do it on the Mackie 1604 and while i'm doing this should both chanel and main fader be all the way down? And if I do this will the DriveRack start cliping before my mixer is at Unity level?

I'm lost here so some help would be excellent. Once this is operational and I can maximize my system for this New Years party with just the gain and crossover settings/parameters for this system. I will then post another question on how to set the limiter and AFS for my perticular setup.

Again thanks for any help and hope you all enjoyed your Holidays.

(Any help on step by step would be great since I be testing the settings onsite couple hours before the gig).....

Comments

  • Can anyone please help to the posting above please....please
  • GadgetGadget Posts: 4,915
    Well its never easy tuning a system sight unseen.. I am familiar with those speakers.. at least the T-18's so here's where I'd start...
    in the wizard set up a 2X3 for stereo 2 way with mono subs.. Better yet you could run the tops mono and bridge the amp since your very underpowered...
    select all custom amps and speakers
    answer all prompts in the wizard then press Xover
    the subs...
    set up a BW18 @ 45hz HPF
    an LR24 @ 120 hz LPF
    the tops...
    set up a [email protected] 120 hz HPF
    give the tops an 8.5 ms delay
    there is no LPF on the DRPA

    You kinda got the gain structure.. but for the main outs its once you have a good strong un clipped channel coming from the channel strips(and panned is NOT necessary) run the gains up till the outputs of the mixer OR the inputs of the DRPA just start clipping..whichever is first.. then use the output volume controls of the xover sections of the DRPA to do the same for the outputs... follow suit with the amps.. once the clip level is reached turn each amp down a bit till clipping is no longer evident.. mark this point, its the max volume tha amps should ever reach..turn the mixer channel inputs down.. plug in the speakers and play a good cd you are familiar with that has good ballance .. like Steely Dan, Asia, Dread Zeppelin, etc and turn DOWN the amp that is creating the greatest loudness.. that is to say if the subs are over powering the tops turn them down...

    Sorry I wasn't here earlier.. its the busiest time of year for me...
    Gadget
  • Hi Gadget thanks for the reply.

    I know i'm underpower on the tops that's why i'm changing my amps the CE4000 to the tops this way it gives 600w to those speakers at 8ohms and I'll be purchasing either the Mackie M4000 or the Peavey CS4000 they both put out 800W at 8ohms perfect for the subs (any recommendations on both of these amps or other?). I'll be running everything in stereo will the recommendations above still work with with a 2x4 configuration?

    Thanks,
  • Hi Gadget, I just received this from EV's tech support.

    I would hi-pass the T18 at or around 40-45Hz depending on the slope that the DBX has to offer. Also I would cross the cabinets over at or around 80-90Hz, depending on the slope. (a 12-24db per octave slope would work just fine)


    If you were to use 45Hz i would suggest a steeper slope. The parameters that I gave you before are merely a starting point.

    To get you exact parameters I would have to take measurements with SMAART LIVE or a software similar to that. I would also need to be in the same room the cabinets are in so I can use my ears and listen to how the parameters actually sound like in that specific room.

    If you use the 40Hz for your subs I would recommend you use a steeper slope. The T18 can get down to 33Hz at a -10db/octave. Also try not to boost the gain up too much or you will also be raising the slope of the filter. By doing so the sub will attempt to reproduce the lower frequencies that the T18 can't reproduce at higher volumes, this could potentially \"cook\" the voice coil in the woofer and/or possibly \"blowing\" up another component.
  • GadgetGadget Posts: 4,915
    I recomended the higher crossover point because you are limited in power...by that I mean that you should have 2-4 times the rated power handling of the speakers. Yours are rated @ 1200 watts short term or peak power. I stand behind my recomendations...though you could go as low as 100 hz.. 80 hz puts the crossover on top of the lo harmonic of the kick drum.

    Either amp will work fine I recomend however you mono the amp, and go 4 ohm for the additional power.. I have 12 of those and I run a pair per channel of a mac 3600 or RMX 4050 and they crank like crazy...

    Gadget
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