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Sleep...is just a crutch.

DFerretDFerret Posts: 66
edited December 2010 in 200 Series Connectivity
Hi to all,

I've ordered the 260 (should be here Friday :D ), been pouring over the site (kudos to all involved, btw), and now have a few more questions...

My main speakers over the dancefloor are operating full-range right now, but have the option for bi-amping (JBL SRX715's). Would you recommend this? What would this entail...running another wire to each speaker, and adding another amp to run the 3" voice coils?

Thanks, Rob


  • GadgetGadget Posts: 4,915
    Re: Sleep...is just a crutch.
    Yep, I'll sleep better when I'm dead... :mrgreen:

    You just won't believe the difference! maybe almost as much as adding the 260!

    You will need one amp for the lows and one for the highs...or 2 identical amps...and the easiest way is with a 4 conductor wire with NL4 connectors. If 2 identical amps are used ... actually tell us what you have OR are thinking and we'll get you on the right track.. My suggestion is identical amps it simplifies things... make sure the amps are capable of delivering the correct amount of power (IF you want optimum sound from the cabs...that is) and that is 2-4 times the RMS (lowest value stated) (like 400-800-1600 watts)value.
  • DFerretDFerret Posts: 66
    I'll sleep better when I'm dead... :mrgreen:
    Yes, the ultimate nap :shock: 8) .


    Right now I'm running all of my main dancefloor speakers (4) JBL SRX715's w/ a Crown XTi 6000, in stereo.

    The JBL's are 800/1600/3200 LF and 75/150/300 HF and the XTi 6000 is 2100 watts per ch 4 ohm stereo, 6000 watts bridge-mono 4 ohm, 4200 watts bridge-mono 8 ohm.

    My subs are (2) JBL SRX 718S w/ a Crown Macro-Tech 5000VZ, bridge-mono.

    I also have (2) EV15's that I use at the ends of the buildings for room fill off the dancefloor, both turned way, way down w/ a Crown 800 CSL. The EV's were part of my old sound system, and I plan on replacing them...eventually...w/ something maybe a little smaller and better sounding (they sound terrible compared to the JBL's).

    I don't run any booth monitors at the moment; my club isn't very big (5000 sq ft), so I can hear and monitor the volume pretty well by ear from the booth (10' up overlooking the dancefloor).

    If I get another XTi 6000, could I run the (4) LF 15's bridge-mono, 4 ohms (6000 watts - 1500 watts each - almost the recommended minimum 2x800 watts operating power) & run the (4) HF 3" voice coils w/ the other XTi 6000 in stereo? Or would it take two more XTi 6000's (2 for the LF 15's)?

  • DFerretDFerret Posts: 66
    I can't f'n wait! The 260 will be here tomorrow :) .

    And I ordered another XTi 6000 to bi-amp the SRX715's (Gadget...I read a few of your posts where you didn't crucify the XTi line, so I figured you'd approve, haha).

    I have a box full of NL4 connectors and I'm ready!! Well, almost...when the 260 gets here I'll figure out what cords and other connectors I still need.

    I'm so excited about the Driverack, I haven't even hooked my new subs up yet (the (2) JBL SRX718S's). I'm still running (2) Cerwin Vega L-36PE's (Junior Earthquake 189JE 18" Cone, 3" VC, Folded Horn Enclosure, 400 watts). I've read your scathing reviews of "grill rattling" direct firing subs (especially the JBL line :oops: ), but I had already bought the JBL's before I found this site.

    The CV L-36 PE's hit hard, and sound great in my club, but I'm constantly replacing the cones (I rotate (4) in and out - (2) at a time). And I have neighbors about 1/8 of a mile away that gripe if we get too crazy w/ the bass...the reason I thought some direct firing subs might be better for us than the folded horns (and the reason I didn't get the SRX728's).

    We'll see...
  • GadgetGadget Posts: 4,915
    The PRIMARY reason I dislike the JBL speakers is:

    1. Cost to quality ratio
    2. (and this is the big one) they are harsh and brittle sounding to me.
    3. I think their low line stuff (TRX, JRX, MRX) is CRAP!

    from what I hear the SRX718's are a "decent" sub that is not bad... but not the best bang for the buck...

    As for the subs.. they are ~so so

    With the Driverack 260 you could have prevented the damage to the Vega's...the failures are most likely a function of the amp power and the gain structure...be sure you get it right... I'm betting too low of a HPF on the subs...was causing over excrusion, and damage...

    As for the XTi's I have only passed on what the folks that do the big shows say about them.. and that is that as sub amps they aren't as "good" as some other offerings.. you may not notice ANY problem what so ever...

    Yes the 260 will help immeasurably, but you still need to do a gain structure and proper system setup.

    Have you downloaded the GUI yet? If not you could have the 260 already programmed and ready to go so all you need to do is download the .dwp file and you would be roughed in and ready to rock. It's also the best way to set up the 260 since you can see graphically what your doing...

    If you want to hook up a newer laptop without a serial port, you will need a usb/serial converter.. the
    http://www.newegg.com/Product/Product.a ... %20adapter
    IO gear unit that has an indication activity on the bus is nice...

    Make sure to make use of the FAQ section as many questions are answered there.. but were here..

  • DFerretDFerret Posts: 66
    Would you recommend something other than the XTi6000? I only chose it, as you said "identical" was easier. I still have time to change my order...

    And, as for downloading the GUI, I have only watched the tutorial (I couldn't find a "training module")...and am still trying to take it all in. I'm taking the crash course in all of this at one time, lol. I've been spending most of my time just learning the basics of a sound system :oops: :oops: :oops: . Our sound system has never been that complicated before, and I've always had someone else mess with it...up until now anyway :roll: . I will download it now...

    Unfortunately, I'm computer stupid, too, haha (but quickly getting up to speed). My pc has a 15 pin connection, if that's what you mean by serial connection... ***(ON EDIT) No, I don't have a serial connection...answered my own question. Ordered the converter, too... 8) 8) .

    Thank you for helping us. I'm not sure why you do this, but thank you 8) .
  • GadgetGadget Posts: 4,915
    Ok, I'll get to this tomorrow ok? Late here...

    BTW the connector you speak of is a monitor (video) output.
  • DFerretDFerret Posts: 66
    Great, thanks.

    Here are some pictures of my current sound sound system...

    Speaker Arrangement:
    http://i1135.photobucket.com/albums/m62 ... G_3204.jpg
    http://i1135.photobucket.com/albums/m62 ... G_3202.jpg

    DJ Booth/Amp Rack:
    http://i1135.photobucket.com/albums/m62 ... 320051.jpg

    Sorry about the mess...the club was still dirty from the night before, but you can see the speaker lay out. The other side of the club is a mirror image of the same components (the club is 90' long, 60' wide w/ the bars dotted along the 90' sides (where it's not so loud). The subs are 65' apart, facing each other, the SRX715's about 45' apart, and the EV15's that I use for fill are about 85' apart (thought I'd like to ditch them for something more appropriate).

  • GadgetGadget Posts: 4,915
    So is the little cage the DJ booth? If so what are the speakers behind it?

    Are the speakers all aimed in the same direction? or are they aimed in at the dance floor? It's kind of hard to see whats actually happening here..were there supposed to be pics of the DJ booth/amp rack?

    Here is the GUI tutorial
    http://www.dbxpro.com/Training_Modules/ ... aining.php

    As you prepare to set up the system know that there are any number of things you can do now to improve the sound.. (did you get the measurement mic?) and the best thing you can start with is a gain structure...

    The FAQ section has loads of helpful stuff..

    JBL has tunings for most of their speakers...
    http://www.jblpro.com/catalog/general/t ... D=18&Run=1
    if they are not in the driverack...that is.

    As to why I do it? well, I got real tired of hearing crap everywhere I went to listen to good music..I worked for years in my local area trying to get the old "Bowl curve" sound eliminated. When the Driverack came alone it was the nexus I had been looking for.

    I have also met some great people from all over the world...and to this day keep in touch with many of them.

    I also am trying to give something back.. paying it forward if you will... one sound person at a time.
    So I guess it's your turn!

    Gadget :mrgreen:
  • DFerretDFerret Posts: 66
    So is the little cage the DJ booth? If so what are the speakers behind it?
    No, the cages are dance cages...they are just crammed full of stools in the picture for the cleaning crew. I built them to house the subs underneath. Here's a better pic...

    http://i1135.photobucket.com/albums/m62 ... G_3225.jpg

    The speaker behind it is one of the (2) EV15's for room fill. The SRX715's blast onto the dancefloor, so we needed something behind the cages (lots of girls cram into the cages :shock: ).
    Are the speakers all aimed in the same direction? or are they aimed in at the dance floor?
    All of the speakers are aimed at the dancefloor. Half aimed due south, the other half north, both straight at the dancefloor. Here's a picture from one end of the building...
    http://i1135.photobucket.com/albums/m62 ... G_3230.jpg

    And from up in the 2nd story dj booth looking north...
    http://i1135.photobucket.com/albums/m62 ... G_3238.jpg

    From the booth looking south...
    http://i1135.photobucket.com/albums/m62 ... G_3239.jpg

    And finally, the booth...
    http://i1135.photobucket.com/albums/m62 ... G_3205.jpg

    The amp rack...
    http://i1135.photobucket.com/albums/m62 ... G_3207.jpg

    And the mixer...
    http://i1135.photobucket.com/albums/m62 ... G_3216.jpg
  • DFerretDFerret Posts: 66
    And, yes, the RTA-420 came in today, thank you 8) . The Driverack is on the Fedex truck :mrgreen: .

    And, Gadget, believe me, I've read every one of the FAQ's...so many times I could recite each of them, but understanding all those words on the other hand...but, I'm getting there :roll: :mrgreen: .

    I've been through the GUI tutorial a few times. The buttons don't scare me anyway, lol. I downloaded the GUI last night, and played with it as much as I could (set the Macro Tech up anyway :) ). When I get all the equipment lined up I'll set up the other amps.

    BTW, I put my amp order on hold until I'm sure I know what I want. I've learned enough on this site to tinker w/ the crossover I'm currently using, so my system doesn't totally suck anymore, haha.
  • GadgetGadget Posts: 4,915
    :) Good job! :) THAT is what we want from any student that wants to learn what we have to offer! :mrgreen:
    I downloaded the GUI last night, and played with it as much as I could (set the Macro Tech up anyway :) )

    I want to stress here that the AMP SENSITIVITY is NOT worth stressing over, and I would suggest using the "start here" method rather than the "amp sensitivity" method for setting up the system 'gain structure'.

    Thank you for reading the information offered, and feel free to ask any questions you have on that info. That is what we are here for. The only dumb question is the one not asked....

  • GadgetGadget Posts: 4,915
    Oh ya... what are you thinking amp wise? Are you thinking another XTi for mids? or subs? With the MAC 5000 there let that do the subs, and if your running fullrange power the JBL's with the 6000, and get another for the power you will need to keep up with the Mac...
  • DFerretDFerret Posts: 66
    Hey, Gadget...

    I posted some better pictures of the club for you (about four posts up). Now you can tear into me about speaker placement :o .

    And, as far as the amps go, yes, I plan on keeping the MA-5000VZ on the subs, bridge-mono. I have it wired 220V and it just idles...I like it :) .

    But, yes, another XTi 6000 for the mids is what I was thinking and then an XTi 2000 or XTi 4000 for the highs...your thoughts? I've been reading what you said about the XTi's and being able to download the speaker tunings directly into the amps. Is this a better way than setting the speaker tunings in the 260, like with the DRPA? Do I really want that technology in the amps if I'm using the 260?

    The weight of the amps mean nothing to me, as you know, since I only have to lift them once, but I do already have the (1) XTi 6000...your thoughts?

    Option 1: XTi 6000 ~ $1400, XTi 4000 ~ $700 = $2100 (2 XTi 6000's on mids, XTi 4000 on highs)
    Option 2?: IT9000HD ~ $4000 (IT9000HD on mids, XTi 6000 on highs)

    Thanks, Rob
  • DennisDennis Posts: 801
    DFerret wrote:
    I posted some better pictures of the club for you (about four posts up). Now you can tear into me about speaker placement
    With that configuration, time alignment is pretty much impossible but I guess the upside is that the DriveRack setup will go faster because of eliminating the alignment step.

  • GadgetGadget Posts: 4,915
    HF 101:
    High frequency sound is far more directional than LF sound which, the lower you go becomes more and more omni-directional.

    As (mostly the horn frequencies here and in these speakers above 2Khz) the coverage patterns overlap there are sonic anomalies that will crop up. Those are cancellations, and modes and nulls. These create spotty coverage on certain frequencies and coverage issues that make the sound uneven and may result in some cases as total loss of those frequencies. Move a few inches in any direction and a whole different set of problems arise. (you have larger diaphram horns that cross at 1200hz.)

    Typically we take speakers horn patterns and try and line them up so the patterns don't overlap... especially on one side of the venue.

    Mid frequencies can be a problem in a 2 way horn loaded speaker, especially when a 15" woofer and a 1" exit horn. The thing is that as the frequency rises, the midrange has a tendency to beam...the bigger the driver the more frequencies will beam...That is of the reasons why a 12" typically makes a better midrange... then say a 15" or 18" driver. It's also why a 1.4" or 2" exit driver that can go closer to 1000 hz will help prevent some of the beaming...

    LF is a strange duck but know that you are almost always better off to place the subs in one location. This offers many benefits, not the least of which is even coverage. If you have any questions check this out:
    http://webphysics.davidson.edu/Applets/ ... fault.html
    move the red dots (SUBS) around and see what happens to the bass waves.

  • DFerretDFerret Posts: 66
    move the red dots (SUBS) around and see what happens to the bass waves
    Holy crap :shock: :shock: :shock: ! I simulated where the subs are now, and then put them together (still off the dancefloor, but coupled together in the middle of the longest wall...and, well, ok, I'm embarassed :oops: :oops: :oops: .

    When I get the new system up I will be placing the JBL SRX718's here (right in the middle of this picture...to the left of the white columns)...
    http://i1135.photobucket.com/albums/m62 ... G_3248.jpg

    And, from what I've read...I should be pulling the (4) JBL SRX 715's back and out away from the dancefloor...more towards the corners of the building, and then angling them in towards the middle 1/3 of the dancefloor...your thoughts? I've read about coupling the speakers on each end, but I want to be careful not to make it too loud in the bar/seating areas.

    Thanks for the the woofer simulation link. That was an eye opener 8) .
  • GadgetGadget Posts: 4,915
    Do you have a floor plan? as I said the pictures make it hard to tell whats going on.

    Were you going to fly the subs then? in the center of the dance floor?

  • DFerretDFerret Posts: 66
    With that configuration, time alignment is pretty much impossible but I guess the upside is that the DriveRack setup will go faster because of eliminating the alignment step.

    Hi, Dennis, and thanks for the reply.

    I am in no way bragging about my set-up . I've already read enough here to know that it needs some fundamental work. I got the Driverack 260 in this morning...sitting right next to me now, but before I hook it up I'm going to go through my whole system, replacing, reconfiguring, etc. whatever needs fixing.

    So, fire away...I'm kind of stuck w/ the SRX 715's (4) of them, and after reading Gadget's last post about the 15's, will scrap the EV15's that are behind the cages. I also have a set of (2) EV12's that I could use...UNLESS...you think I'd be better off w/ just the (4) JBL SRX715's...reconfigured??

    BTW, the SRX715's will be bi-amped.

    Thanks again, Rob
  • DFerretDFerret Posts: 66
    Were you going to fly the subs then? in the center of the dance floor?


    No, I was planning on leaving them on the concrete floor, side by side, about ten feet away from the dancefloor. ***(ON EDIT)...Actually, I'm going to stack them on top of each other. They look good, and I want the girls to be able to fondle them, lol.

    I'll draw up a floorplan and try to attach it.

    Also, what were your thoughts on the amps...another XTi 6000 for the mids (two total including the one I already have), and an XTi 2000/4000 for the highs?

    Thanks a bunch :) .
  • DFerretDFerret Posts: 66
    Okay, here is the floorplan of my club (it's not pretty, but it's to scale :wink: )...

    http://i1135.photobucket.com/albums/m62 ... tled-1.jpg

    The red box is the proposed location for the (2) JBL SRX 718S's, stacked.

    The blacked-out areas are the bathrooms and the entrance, both of which the walls go all the way to the ceiling. The black circles are 24" round tables (chairs not shown). The (2) small squares are the dance cages at each end (where the previous Cerwin-Vega subs were - and will stay, wired up but unconnected, as back ups to the JBL's).

  • DennisDennis Posts: 801
    Where are the speakers??
  • DFerretDFerret Posts: 66
    Where are the speakers??
    Hey, Dennis...they are at the long ends of the dancefloor right now, but I'm moving them, so I didn't draw them in.

    My goal is to reconfigure the (4) SRX 715's and not even use any others.

  • DFerretDFerret Posts: 66
    Typically we take speakers horn patterns and try and line them up so the patterns don't overlap

    Okay, I've researched this as much as I can and have come up with two different arrangements for the (4) JBL SRX715's.

    I will get them scanned and see what you think.

  • Okay...sorry for the delay...but after reading so much about about speaker placement, I couldn't stand it another second and had to move my speakers :lol: .

    Here's what I did for now...

    http://i1135.photobucket.com/albums/m62 ... urrent.jpg

    And here's what I'd like to do after adding the 260 and bi-amping the 715's (picture suggests adding another SRX 715)...

    http://i1135.photobucket.com/albums/m62 ... osedII.jpg

    But, anyways...on to the Driverack :twisted: . I ordered another XTi 6000 and an XTi 2000...they're on the UPS truck as I type this 8) . I also ordered all of the input and output cables (had them made down in Austin, TX by Hooked Up Cables...nice people).

  • GadgetGadget Posts: 4,915
    Well, the second pic is starting to look like it will offer a lot of benefits...the first will be right in the middle of the pattern overlap nightmare...(cancellations...phasing...nulls...)

    Where are the subs?
  • Hey Gadget,

    I knew you'd like the second one 8) . I drew that plan up the first time with only (2) speakers in the center, but thought (3) would be better (have read a little about the 3 speaker cluster).

    How would I wire the (2) XTi 6000's and (1) XTi 2000 w/ 5 SRX 715's?

    Oh, and the subs are the red box against the wall. I'm still using the folded horns, but I moved them to where I'm placing the JBL's.

  • GadgetGadget Posts: 4,915
    problem is..your speakers have a 75 degree horizontal coverage (horn) and 2, makes 150 degrees...3.. well more than the room can support.


    Dennis :?
  • I did draw it up the first time w/ just (2) in the middle. I actually measured the angles and sketched them out w/ that same arrangement...seemed to work...I just thought (3) in the center would be better than (2) (just being greedy :lol: ).

    I'd post the scale drawing I made, but I drew it by hand, and can only get it into pdf on my printer.
  • DennisDennis Posts: 801
    Gadget wrote:
    problem is..your speakers have a 75 degree horizontal coverage (horn) and 2, makes 150 degrees...3.. well more than the room can support.


    Dennis :?
    The 75* horns will always have a comb issue when overlapped but the question is, how big of an issue is it? Sometimes it is a nightmare and sometimes it is a minor issue...it would be cool to run a prediction on it. Im sure it's already been listed in this thread somewhere but what are the components in these speakers?

    A bigger issue for me would be to having all of the sound moving in one direction. I am not a fan of either of the two posted designs but if design number two mirror imaged the two outfill to the other side of the dance floor, it would be a lot easier to time. Of course there is still the issue of the 3 speaker overlap but if it is an issue at all, I think it is an easy fix.

  • DennisDennis Posts: 801
    The following images are predictions of speakers with 80* horns (the closest I could come to 75*). The first 2 are center clusters of two and three speakers. They both suck with much comb action. I tried many splay angles and it helped very little. The third is 4 speakers all aimed the same direction with a minor comb running down the center and as far as I am concerned, a non issue. You decide.

    All predictions were taken at 2kHz


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