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DAS Audio PA set

edited January 2012 in PA Configuration Wizard
Hi, I'm John and I would like to hear your advice about the settings on my drivereack PA sound system.
I have the following material (http://www.dasaudio.com/index.asp?pagin ... ducto=2659).
High-mid: DAS Audio R215
Sub: DAS Audio ST218.
Low Amp: Carver PT 2400 (2 x 1200 watts) Mid Amp: Carver PT 2400 (2 x 1200 watts) High Amp: Yorkville P-3000 (enough)

The tweeter is a 2-inch 150-watt horn loaded (recommended crossover frequency 1200 Hz) Furthermore, twice a 15-inch mid / low of 1000 watts total.
This is all front loaded.
The sub is a horn loaded 2 x 18 inch, 1250 watts total.

Best regards from the Netherlands


  • GadgetGadget Posts: 4,915
    Hi John,
    Greetings from Northern Minnesota, USA

    I guess I have some questions...I have been a fan of D.A.S for some time but am completely unfamiliar with those models... The closest thing I have seen is the ST182 As for the tops, what series are those? I don't have any R series listed in the D.A.S. product line. I'm most familiar with the RF series.

    The things you posted have pictures only...no useful info.. I need information, especially about the subs. I didn't know D.A.S made horn loaded subs?

    This will help us make recommendations, although the DRPA doesn't have enough delay to be of use for most horn loaded subs.

  • DraDra Posts: 3,777
    "2 x 18 horn loaded sub"?
    Do you mean that they are mounted so that the baffles are angled to the center and the cab forms a "horn like" shape?

  • It took a little digging but I found it. Download and unzip from this link for the ST218:

    http://www.dasaudio.com/index.asp?pagin ... ducto=2658

    Look for the ST218 folder and click on the Acrobat Reader file called "te_st218_04".

    The link in the OP actually has the info for the R-Series... just follow the same course for the R215 info.
  • Dear all,

    In response OklaPony, this is the set that I have. If it worked, I also have two PDF files put there. If you need further information I would like to hear what information exactly.

    From DAS Audio is a crossover from analog (CT-2000). This is a Linkwitz-Riley 24 dB / Oct filter. Tilting at frequencies 125 Hz and 1200Hz.

    The ST-series released in europe (touring sound) was the top series from 2004 to 2008. The sub was the ST218 ST-215 horn loaded top of the R-215. The ST-215 has the same components as the R-215 (reference series), but in a horn cabinet built. This makes the ST-215 larger and heavier than the R-215 peak.

    Returning to the sub cabinets. This contains two 18-inch 600 watt speakers. Here in Europe we call the construction of the cabinet a W-Bin, or folded horn. It comes down to the front of the speaker facing rearwards in a compact sealed cabinet. The sound must now get back to the backplate and then to reverse direction and go to the dance floor. The speaker is right, not directed toward the center.

    Well, my english is not so good, so I hope you understand my story.

    Greetings from Geldermalsen, Netherlands
  • edited January 2012
    Now with the pigs.
  • GadgetGadget Posts: 4,915
    John, your English is fine...

    As soon as I saw that I was like ???? :?: :?: :?: W bin? That's an old technology that fell out of favor over here years ago.. Sorry john NOT knocking your subs but here, now... the new IN thing is tapped horns. They play lower, and louder than almost any other technology available.

    Ok that means that the horn path is NO longer than the long axis of the side of the cabinet... (plus a little.. maybe...) so 33 inches deep?? (the delay here would be about 3 feet...PLUS propagation delay...)

    Without measurement equipment (and the skills to use them) your best bet here is to use the subtractive method. That is, select the crossover frequency ( horns sound honky above about 120hz in my opinion) so as below, play a fre3quency at the crossover frequency point (in this case 118hz) (note a signal generator or audio CD with the frequencies is necessary for this purpose) reverse the polarity of ONE OR THE OTHER of the component(if in this case you choose the mids you can do BOTH the crossover points at one time!!) in the frequency band (reverse either the subs or the mids... but not both) this will have BOTH components playing the SAME frequencies...NOW, sweep the delay till the LEAST sound is heard at the crossover point...THIS is the rough delay for the crossover point. NOTE: having both at about the same volume will help.

    Now play a 1200hz frequency, and sweep that band as well and find the null...That is the rough delay for the MF/HF point, and you can reverse the polarity back to normal of the mid speakers.

    So, the factors for deciding the xover points are... Mid frequency power, and you are short, even if you have an amp for each pair of MF 15" speakers...But you are under powered for the subs as well, Therefore I would:

    1. Set the HPF for the subs @ 45hz BW18
    2. Set the LPF for the subs @ 118hz LR24
    3. Set the HPF for the mids @ 118hz LR24
    4. Set the LPF for the Mids @ 1200 hz LR24
    5. set the HPF for the horns @ 1200hz LR24
    This could be a stereo bi-amp With mono subs, or Stereo bi-amp and stereo subs...in the mono config the subs are summed but both low left, and low right outputs WILL produce sound...

    This config takes into consideration the power you have available, If that power changes, the xover points can change...

  • Google translator helps good I hear.
    Gadget thanks for the tips. I had the frequency of the subs already from 120 Hz to 100 Hz lower, I'll see what the 118 Hz do with it. The way of setting the delay I will definitely try.
    I am wondering if there are further hints in adjusting the equalizer. I have no RTA mic.
    To test it, I had a Shure Bata 58 lie along a measurement that I have done. The difference between the neutral and the shure measurement is enormous. Are there good alternatives to the RTA mic, I also have a "Rode Broadcaster" to try.
    Last question why a BW18 HPF for the subs? What is the idea behind.

    I like to hear the experience of my American colleagues
  • Here are some details of the R-215 top
  • GadgetGadget Posts: 4,915

    For measurement/Auto EQ process just any microphone will not work....The problem is what we need is a known flat as a ruler response mic so that we aren't having to deal with trying to deal with the mic's response as well as the system... The cheap mic's are generally usable and flat from 100hz to 7000 hz where the most critical frequencies are, they generally are less flat above and below this area...If you look up the mic you used you'll see that it's anything but flat with a presence peak in the vocal range.

    As we discussed before, you are under powered by quite a bit...especially on the subs, so the 45hz BW 18 filter is a type that has a pretty steep "knee" and helps protect the woofers from over excruding...(moving so far as to damage the voice coil by having it run into the mechanical stops ...like the magnet back plate, or over stressing the surround and spider...) note here that sub bass takes a LOT of power, the lower the frequency, and more power is necessary to drive the cone to that frequency. That is the reason for the HPF 145hz as well. If you had the recommended power available, even the Program rating you could lower the HPF to 35-40hz and probably be ok, but with 1200 watts...

    Speaking of that, are you running just one amp for the subs? So, 2X1200 watts? that would mean that there is only 600 watts per woofer...

    I noted that the recommended xover for the horn in the box (passive crossover) is set @ 1.25khz @ 24dB/octave... the active crossover points I supplied should fall right in line with those specs. Active crossovers like the DRPA+ usually exhibit a bet better control of the xover point than passive counterparts.

    The 118hz is specified but just get as close to 120 as possible.. as I recall 120 isn't available in LR24...

  • Dear Gadget,

    I understand the problem with the mic. I was hoping you had another tip of the biggest mistakes to adjust. Everyone has their own adjustment, but how do you set it neutral?

    Returning to the amplifiers. It is about two times a Carver PT-2400. It indicates when both channels are driven on the entire frequency range an average of 1200 watts for each channel. 1250 watts for each channel with ideal frequency range, but I do not count them.
    One PT-2400 is now on the two ST218 units. Each channel its own sub cabinet. The other PT-2400 is connected to the 2 x 15 inches of R-215. Again each channel has its own 2 x 15 inches. I also have a Yorkville P3000. This amp is too powerful for the horn of the R-215, but I just have no other amplifier for the high. This is a temporary solution.

    Is it really better to have a PT-2400 fully sub cabinets to connect. The other PT-2400 to mid cabinets.
    Or is it better to have a PT-2400 can be connected to the left (on the left channel a sub cabinet line, then the channel b 2 x 15 inch mid line) and the other PT-2400 on the right side?
    I can imagine that it increases the load on the power of the amplifier is better distributed.

    I like to hear your response.
    Here from a windy Netherland
    John van Doesburg
  • GadgetGadget Posts: 4,915
    Hi John,
    It's -20 C here (not considering the wind, the wind is up to 50KPH and the night is yet to come...going to be a cold one tonight!

    I read an article recently that trying to tune a system without measurement tools, and skills...is like trying to figure out what bacteria look like without a microscope.
    John, I have been doing this for so long that I can tune a system by ear pretty well...that doesn't mean it will be flat..you have the tools, except for the mic, I don't know about over there but we can get a mic that will do the job well for well under $100USD...

    Now, if DAS audio has a speaker that is Bi-ampable as manufactured they SHOULD provide tunings for those speakers...I assume that their proprietary processors are the reason they don't want to do so... also, recent developments on that subject have resulted in the knowledge that cross platform implementation of tunings developed on a given platform will NOT result in consistent results on platforms other than the one it was developed on. What that means is that if DAS developed a set of tunings for those tops of yours, they would NOT be the same when implemented on the DRPA+... not only that, but tunings developed for the DRPA+ won't be the same when entered into the DR260, even though they adr both dbx products...

    So, you have the tools to do the job yourself (to a certain extent). If you want to REALLY set them up properly, that would take as I said measurement tools and the skills to run them. Tools like SIA soft SMAART, or Systune, Praxiteles or Spectra foo...unlike the driverack that only uses loudness based frequency adjustment, the others use time, coherence, and other factors to make sure that the speakers energies are in phase, time aligned, and spectrally neutral.

    On the other hand, the driverack platform can make a BIG difference WITHOUT all the expense, and training, the above tools have MASSIVE price tags, and or steep learning curves to even be able to decipher the data...

    So, as I see it your options are, get the mic, tune the system yourself without it, or get SMAART.. and spend loads of time and money to get the results that might only be marginally better than the driverack can do... with the mic, and the techniques we have developed here...

    Now, as for your power situation...Look, you have (on paper) only 600 watts going to each of those LF speakers...you could throw 4 TIMES that much power at them short term...for subs to REALLY get going they need power, and lots of it...for live sound it's not unreasonable to put those subs with an amp capable of 2400-4800 watts. Now granted the 4800 watts is a momentary number only, but it's called headroom. If however, you are playing back todays heavily compressed popular music you would want NO MORE then the rated program power.

    If it were me, I'd be using at LEAST a bridged 2400 per sub, as for the amp for the horns.. simply turn the input gain down... I have a car that WILL do over 120 MPH...doesn't mean I HAVE to go that fast though...

    John have you read the "Start Here" thread, or the "FAQ's" ?

  • Here again a message from the Netherlands.
    Again, thanks for thinking along.

    Returning to the amplifier power. I understand that the amplifiers never have too much power. Still, I wonder why I rarely see here in Europe there is too much power. In 1997, my old boss bought a new DAS soundsystem. This was the predecessor of what I'm standing. There sat in amplifiers (DAS Audio P-1800) which only 900 watts at 4 ohms, any ending. The sub was still 1000 watts instead of 1200 watts now.

    I am looking if there is an alternative to the dbx mic on the forum. Does anyone have any suggestions please let me know.
  • GadgetGadget Posts: 4,915
    Ok so was there a question about amp power? If so, here is the rule of thumb...
    Live sound re-enforcement:
    2-4 times the RMS value of the speakers...and that's what the spec sheet says. 1000 watts RMS, 2000 watts program, 4000 watts peak
    that peak rating is an INSTANTANEOUS... for only milliseconds of time ... and is considered HEADROOM

    Recorded music playback:
    in your case, 2000 watts...

    So about the Mic...

    ANY ruler flat mic will work
    Behringer ECM8000
    Rational acoustics RTA 420
    Beyer dynamics
    Radio Shack
    to name a few...

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