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delay parameter

rickrockrickrock Posts: 27
I can't get the data wheel to change the delay in output 5 in the post crossover eq. (I'm running the subs mono from this output.) I push it \"on\", and push it to \"fine\" not coarse, and I push my units to seconds, not feet. When I try to adjust the 0.00 to something else with the data wheel, nothing happens. The sound guy we used last year struggled with this too, and said something about this module not having been installed at the factory, but he did get it \"installed\" or otherwise working.

Well, now i've gone and done it--I saved over his settings, and i can't get the data wheel to move that 0.00 at all. All i really want is .92 ms of delay on the subs. Interestingly, when I hook up this laptop with the driveware software, the two post cx \"D\"'s representing the post cx delay modules are in red, not white like the rest, and they will not open when I double click, unlike the rest of the modules which I can program pretty readily.

I didn't think something like a .92 ms delay on the subs would make a difference, but I could hear it, it make the srx 718s and the 722 top boxes sound like they were all one hi-fi stereo speaker.

Help !

much obliged,
rickrock

Comments

  • rickrockrickrock Posts: 27
    Sorry, not in the \"post crossover eq\", typing too fast, just in the post crossover delay module.
  • DennisDennis Posts: 801
    Open Driveware.
    Left click \"Config\".
    Right click on a \"Red D\".
    A drop down menu will appear.
    Select an adequate maximum amount of delay for that output. (eg 100ms)
    Repeat with other \"Red D's\".
    Left click \"Config\".
    Left click \"Yes\"
    Double left click on one of the output delays you just reconfigured.
    Set delay as necessary (eg .92 ms).
    Repeat if necessary.

    Dennis
  • rickrockrickrock Posts: 27
    Thanks a bunch. Worked as advertised. But I've learned the .92 must have been set at the pre-CX delay module, because that's the only one that allows fine tuning in those increments, the post CX only allows, e.g., 50ms, 100ms presets. But you handed me the keys, thanks.

    rickrock
  • DennisDennis Posts: 801
    I think you have missed a step.The drop down menu is only to set a range of delay. You can't dial in your .92 ms until you exit \"Config\". If I haven't answered your question, please list all of the steps you are taking prior to hitting a dead end with the post XO delay.

    Dennis
  • GadgetGadget Posts: 4,915
    If you choose the 20ms delay amount you will be allowed .21, .40, .60, .79,and .100ms...etc.. if you choose the 50ms then you get... .50, .100...ms times.
    G
  • rickrockrickrock Posts: 27
    edited May 2009
    Ok, I'm going to give it another try, and choose .20 and work from there...

    But as I am trying to get back to a setting someone else put in, (which I liked), I have to confess, I'm not certain which of the modules he had the delay put in. I'm remembering he told me he wanted to delay the subs a bit, and the pre-cx delay is does not pinpoint the subs, if I am getting it.

    Is there are rules of thumb here, or a 'best practice' that says when fine tuning a jbl srx system, you want a little delay on the subs in the post CX module? That would help give me a little confidence anyway,

    much obliged
    rickrock
  • rickrockrickrock Posts: 27
    Excellent, worked exactly as described. I needed to know these are maximum selections, and now I do. Choosing .20 ms took me where I needed to go.

    So i do have the output 5 at .92 ms of delay, so the subs will be delayed that much. Does that strike anyone as just wrong, (ooh, that's just wrong...)? I'm pretty sure that's where it was.

    much obliged

    rickrock
  • DennisDennis Posts: 801
    OK...now that I understand the original problem...it don't matter what range you are in. After you configure and exit config, Double left click on the output delay. A window opens up. Toward the bottom of the window is the word \"length\" and to the right of that is a horizontal slider and to the right of that is something like 0.00ms. Click on 0.00ms and it turns yellow. At that point, use left arrow and right arrow to scroll back and forth .02ms per click.

    .92ms may or may not be correct. Without running the tests, I wouldn't know.

    Dennis
  • GadgetGadget Posts: 4,915
    So, then IS it right to delay the sub? well, jbl doesn't use it on their presets...However, Jack Alexander... frequent FOH, contributor and erstwhile \"controversial\" character/instructor in Chicago applies delays frequently...He insists that he (and his students) consistently come up with various delays for the different components of DSP processed systems... Mike Kovach measured the LR24 mid-hi / sub xover @ just under 7.5ms...on the Driverack.

    I delay my lo mids to my LABsubs about 18.5 ms which is understandable since the labs are about 10.5 feet of horn length... and then there's the propagation delay...and ????

    your mileage may vary...what sounds right ultimately IS! Let your ears be the judge!
    G
  • rickrockrickrock Posts: 27
    Thanks to all for the help. I can \"configure\" the post cx delay module now just as described.

    You're right, it is a function of what sounds right, and that little bit of delay did the trick last summer (we tend to get the big rig out for the summer outside gigs). The guy we had help us last year said he had a few tricks up his sleeve from talking to jbl guys--one of which was this slight delay in the subs. Another was a PEQ setting, where he ratcheted down maybe 2dB of 658 hz in both the highs and the mids--same setting to both even though the highs were crossed at somewhere around 1.16k. He said this was a jbl engineer recommended 'trick' that is not in the PEQ presets for the srx 722's, as was the .92 ms delay. Little improvements that made a big diff in the sound.

    You guys are a great help, and it's great to have you here. Next project, buying a second 260, a second sub amp and splitting my amp stacks right and left. This is as much a way to help our aging backs as anything else.

    much obliged
    rickrock
  • DennisDennis Posts: 801
    What is the purpose of the 2nd 260?

    Dennis
  • rickrockrickrock Posts: 27
    I think the idea is to make the system somewhat modular, small scale what is done in larger rigs, one amp rack per side.

    The first 260 would receive the \"left\" input, and send out hi mid and lo to the amps in that rack, and the second 260 would get the \"right\" input and do the same in that rack. With that configuration, we have one cable coming from FOH to the left and one to the right, each with its own 260 and amp rack. Otherwise, you have two cables going to one amp rack, with the 260, and three xlr cables (high, mid and low) across the front of the stage to the other amp rack (or with mono'd subs, only two, with the speaker cable for the subs going across for the lows).

    Yeah, cables are cheaper than a 260, but don't you lose something in that cable run, say 30 feet from the 260 to the other side of the stage's amp rack? Anyway, this is what I've heard some of the rental houses do with their small to mid size rigs. I'm always learning here, which is why I mentioned it, so take aim and fire.
  • DraDra Posts: 3,844
    A 260 in each rack? Yes, If you need a rack at two different venues.
    The signal loss is infinitesimal. Run the cables to the other side. If you plan on controlling the (2) 260's from FOH with the GUI.... think again. Can't do it. One at a time only. Sorry.

    DRA
  • DennisDennis Posts: 801
    Yeah, what Dra said. I usually see the processor at FOH with the console. The DR260 would require a 6 ch drivesnake (return lines) run to stage to one of the amp racks. 3 of the channels would go to that rack and the other 3 would extend across stage ( through the use of a 3 ch cross stage snake) and connect to the 2nd rack. At line level, a 200' - 300' snake run will not have any signal loss. Speaker cables are another story.

    Dennis
  • DraDra Posts: 3,844
    I 've had the 260 at FOH and in the amp rack. I started at FOH. Moved to rack. Now back at FOH. I had set-up changes and need changes during these moves. Now I have it where I want it.

    FOH:
    Pro's -
    If it locks up for some reason, you can power it down without running to the stage. (That's a pro? :roll: )
    Access Auto-EQ. (You don't want to have to go to the stage during a show to use it. :shock: :lol: )
    Con's -
    Depending on set-up, may take up too many snake returns. (Stereo 3-way needs 6)
    Unlabled patching can cause problems and damage.

    Amp rack:
    Pro's -
    Amps can remain patched.
    For the most complex set-up a maximum of 3 snake returns are needed. (including GUI control line)
    Con's -
    GUI is \"mandatory\" for any control at all.
    GUI special cables for snake use must be made.
    If it locks up for some reason, you can't power it down without running to the stage.
    You have to go to the stage to use Auto-EQ.

    There is no right or wrong. Only what fits your needs.

    DRA
  • DennisDennis Posts: 801
    After reading Dra's post, I'm thinking my previous post didn't explain things clearly. I had suggested a separate drivesnake that would be fan to fan. It would connect directly to the 260 on the console end and it would connect directly to the amp rack on the stage end. You would not have to patch from the \"snake head\" to the amp rack with mic cables. A multipin connector would be even faster.

    Dennis
  • DraDra Posts: 3,844
    Dennis, Even though I did think that you were refering (not reefering :lol: ) to a rack to rack stage jump, my response was to your statement about the 260 being at FOH, and was for Rick's benefit.


    DRA
  • rickrockrickrock Posts: 27
    That dialogue was helpful---and it saved me $700+/-.

    We'll never get to the point of putting the 260 anywhere but in the amp rack, because it doesn't get used on the fly. We just need the speaker PEQ tunings, crossover, RTA auto eq room pinking, AFS, and that little delay we were discussing, so my crowns and jbl's work together well. We're weekend warriors, playing fundraisers and country club gigs to crowds of 200-400 for the most part. But we do get compliments on our sound. So now I'm trying to get both sound and logistics working together, and two lighter amp racks seems better than one heavy one. There is also the fantasy that with two racks, each tricked out with lo mid and hi amps and a processing unit, I'd have the making of small rental co, and could use both or either as needed. (I also happen to have 2 10 space racks not otherwise being used right now--except as spacers between the 718 and 722 on each side.)

    Anyway, you guys are invaluable as usual. Thanks for the help.

    rickrock
  • GadgetGadget Posts: 4,915
    I like the idea of a rack on each side.. and if you DO get into the rental business you can always add a second 260 as money and rentals permit...keep those speaker cables as short as possible..

    :wink:
    G
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