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Drive Rack PA or 260



  • My DR260 arrived today. Been doing alot of reading since my last post. Some things are becomming clearer. We have band practice tonight so I'll have to wait until tomorrow to play.

    Question: What is the recommended mic for the RTA? I did not recieve one with the unit :(

  • GadgetGadget Posts: 4,915
    1. Audix TR240
    2. DBX RTA M
    3. Behringer ECM 8000

    It's all in how accurate you want things to be...

    The only unit that comes with the mic is the PX...

  • DennisDennis Posts: 801
    Earthworks M30

  • GadgetGadget Posts: 4,915
    HMMMM :?:
  • DennisDennis Posts: 801
    You feel that's a tad excessive?

  • GadgetGadget Posts: 4,915
  • I have my DR260 up and running :D
    I did the gain structure for the Tops, Subs and Monitors all the way through to setting the channel limiters. I was surprised to have to set the Monitor Amp so low (only 1/4). It still seems to be pleanty loud and clear. I used a pink noise wave file downloaded from a link on this site. Thanks for the great help!!! I know I have to balance the amps (Tops/Subs) so I'll do that next.

    Gadget I still need a little guidance. :roll: I'm using the file with the crossover that you sent me and the gain structure is complete. I have played music through the system and it sounds good. The only changes I have made to your file are the input gains and limiter setup during the gain structure setup.

    What should do I do next :?:

  • GadgetGadget Posts: 4,915
    Wally, those were and are starting points... have you read the \"read me first before posting\" section? Filled with excellent tips and tricks...If your DR is @ unity, and thats where the numbers fall...so be it...the gain structure is what it is... you can however use the \"amp sensitivity\" method, you WOULD however need to adjust the xover levels of the DR to compensate...If you want the best of all worlds, channel faders @ unity, mixer master level meters at/near unity, and amps @ sensitivity rating (in a perfect world, or with a perfectly MATCHED system...got one?)

    Next step is with the mic...I assume you still don't have one?.... speaker flattening is next...after making sure all drivers/speakers are working together (moving the same direction at the same time with a positive input)properly crossed and positioned with respect to the room...(if that raises a question or two... see the RMFBP section...

  • I have gone through the Read Me First and other sections (several times). I have learned a great deal, and forgot even more :oops: . I hope to get a mic tomorrow and do all of the speaker tests. I'm sure that will raise more questions.
    Thanks again....
  • I had to order my RTA mike online. The local music stores don't have any in stock and were unable to give me a delivery date :x I'm paying more than I should for it, but want to get underway.

    This is a quote from the indoor speaker flattening method.
    I did this with my new 12\" coaxial tops, (as you can see in the pictures) and I was able to store High precision setups for -0-, A, C, and D, precurves in about 10 minutes, and that includes a couple passes @ -0- (flat) to get as flat a response as possible using the PEQ's with no \"GEQ\" equalization.

    1. If we are going to transfer the GEQ settings to the PEQ's, why don't we just look at the RTA display and adjust the PEQ's accordingly to flatten the speakers?
    2. What is the Auto EQ doing that we can't do manually with the RTA display and the PEQ's? I know I'm missing something here :oops:
    3. What does A, C, and D, precurves mean? Direct me to reading material if its complicated :wink:

    Thank You
  • GadgetGadget Posts: 4,915
    Hi Wally...
    Great to see that your taking this seriously... BUT your reading too much into it...
    1. Ya... that's the whole idea...and if you think you can discern enough from instantaneous displays of frequency based information on the RTA then your WAYYYY better at this than I am...I admit I do watch the RTA display in real time (260 on up) and make judgment calls on what I see... but there is WAY to much going on to be able to say .. oh ya... look.. there it is.. a 3db cut @ 121hz.. hits the same EVERY time...
    2. The Auto EQ is using the allband output (pink noise) to determine the exact amount of information being reproduced in any of the 28 ISO centered frequency bands...THEN.. adjusting that band... I.E. 500, 630, 800, 1K, 1.25. 1.6khz... but what if it's 545hz that's the problem? Maybe 910hz or a 4.65k squeal? these are real world problem areas... that aren't covered by the GEQ...what then? way too often the problem doesn't fall right on where the engineers set the center frequency...A PEQ can hit the nail right on the head...(or within a few hz... not HUNDREDS.. or thousands...) So how would you do it?
    3. The presets ARE:
    A. -0- flat preset... all frequencies represented equally...NONE hyped or cut...
    B. The other presets are ones that cut or hype certain frequencies (those that are covered anyway :roll: )...The manual (used to) give visual representations of what they \"look\" like... some cut the mids and hype the lows and highs like the (C) curve.. I guess they don't represent the various curves with a graphic picture any more.. I'll see if I can get anything from them on this, BUT As I said... with the \"new indoor method\" you can do all with in a few short sessions, and compare the way they sound...some I have used for speech, some for classical music...I prefer (HANDS DOWN) the flat preset!

  • DraDra Posts: 3,777
    I'll answer it a little differrent. The Auto-EQ is faster than you are in most instances. While you are trying you see where the freq bar is peaking to make an adjustment, the Auto-EQ has done it and moved on. An advantage to maually doing it is that you might see a bar with a lot of fluxuation, which may tell you some fishy is going on (phasing, reflection cancellation, etc). Whether auto or manual, there are problems and limitations inherent in the system itself, expecially indoors.
    I'm not sure if it is easier to flatten with GEQ and then transfer to PEQ or go straight to PEQ.

  • Ahhhh I see. Another light blub has turned on. :idea: I'll soon be bright enough to... to.... well, maybe to not have to ask so many questions. :D
    Thanks again guys.
  • I plan to use the Indoor method for speaker flattening, but have a few questions before I start. :?: :?: :?:

    1. Do I use my normal user program during the flattening session? I assumed I would, but in other posts its mentioned that the tops were done at full range. Wouldn't my crossover cause Auto EQ to drive up the non existant low Hz if I'm just doing the tops? I was just going to ignore anything below the crossover point and transfer the rest to the PEQ for the tops.

    2. My 2 tops run in mono and are in parallel on the same amp (on the same DR output). Should I flatten just one top and assume the other is the same? Do one top at a time and average the results? Do both tops at the same time?

    3. Should I bother with the subs?

    4. I see there are 4 bands of Post PEQ's per output channel. Is is safe to assume that if I require more than 4 for speaker flattening, the speaker likely sucks, or I did something wrong? :oops:

  • GadgetGadget Posts: 4,915
    Hi... you have lots of questions... :lol::lol:
    BUT thats cool! we are here for just that reason... guys .. feel free to interject any time. (as always)
    1. Yes. use the normal user preset for the tuning session... the point here WAS that the Auto EQ is MOST usable between 170 and 700 hz... the rest is VERY susceptible to room affects, and is not \"universally\" reliable\"
    2. Well we don't want to assume anything... and god knows the crap they are putting out today needs all the scrutiny you can muster...but where do we draw the line? I assume nothing and examine all the parameters... your mileage may vary...
    3. I usually (nothing is EVER \"ALWAYS\") do the subs by ear/ memory/ measurement...
    4. No...that isn't necessarily true...some MAJOR MFG'rs require a LOT more than 4 PEQ's per channel... just because they require this does NOT mean they are CRAP ... just that they need those to KEEP from BEING crap :lol::lol::lol: BUT then again>>>> :roll: (see Danley sound)

    Can a $5000 speaker really BE crap?
  • DraDra Posts: 3,777
    I know that you like light bulbs :idea: ...
    Doing the full system will help you see problems at the x-over point to the subs. Might need a wider spread, perhaps an over-lap, or a different point altogether.

  • Thanks again for the insight guys. I'm on the road to being a 2 bit guitar player and a 64 bit sound guy : :lol::lol::lol:
    (or is this thing 128 or 256 or 512 or 1024 .... doesn't matter, it works and sounds great)
  • Well I did it!!! I used the indoor speaker flattening method. And my system is drastically improved!!! At least it sounds great playing a Toto CD :lol:

    Questions: :?
    1. Speaker Flattening - Tops - I only applied the GEQ to PEQ in the 170 to 700 frequency range . Is this correct? I was not sure if that range was suggested for Speaker flattening, EQing a room, or both.

    2. Is there any before and after screen shots from anyones speaker flattening sessions posted anywhere? I would like to see how flat they got their system. I still get up to +/- 4 on some bands of the GEQ using Auto EQ (after moving the previous settings to the PEQ).

    3. When I move the GEQ to the PEQ are the changes immediate or do I have to store the settings before running another Auto EQ?

    4. Where would I report system and software bugs? There are a few cosmetic things that should be fixed in the next software/firmware updates.

    Thanks DBX for a fantastic product
    Thanks for everyones help on this site
  • DraDra Posts: 3,777
    The 170-700 rule is mostly for an indoor room setting because of reflections and cancelations and doesn't generally apply to flattening sessions. Personally I have not been very happy (secure) with the results of the indoor method. YMMV.
    Saving is not required, but is a good idea. You said +/- 4db after, what was it before and what change did did you make? It will typically take multiple passes and quadruple cahnges to get to set right. PEQ's act differently than GEQ's.

  • Dr. JDr. J Posts: 209
    Hey noize -- having some fun with the RTA? I thought I was gonna need some new horns by the time I was done. :shock: :D I believe the 170hz - 700hz range was more for running the RTA AFTER you flattened your system in a room that is hopefully decent to begin with. BUT -- it may not be all bad though. The idea is to go after the biggest offenders first. Don't be afraid to crank up the gain on a parametric if you have to to get the GEQ to level off. Just work through back and forth until the biggest ones level off and then work from there. The low frequencies may be boosted & your highest frequencies may be boosted. Not to worry -- your system may not go that low or that high. Don't waste a parametric on trying to get that 30hz in line because your subs may not go that low. 30hz is low! Right G? (LabSubs) So I didn't put too much emphasis on those. The 170hz to 700hz that you read is from a white paper that Mikey Kovach did on the Smaart system side by side the DriveRack. The DriveRack kept up pretty good within the 170hz - 700hz range. Outside of that -- there were too many inconsistencies. So you want to keep those readings BUT keep in mind running the RTA in a bad room may just make it worse. You could try it and see -- tune the lower and upper frequencies by ear. I haven't done the RTA pass inside a venue yet because I know these rooms aren't very good to begin with PLUS there is always people in them and you will just make everyone mad before you get your medium to high precision pass completed. Good luck!
  • Dr. JDr. J Posts: 209
    Before the weather got much warmer here I did the indoor method and got my tops pretty flat --- they sounded much much better. Once it got nice out I took the whole stack out and did a flattening session. Saving it as \"Outoors\" and the other as \"Indoors\". I then compared the two results and I can't explain it but the parametrics were very different from each other. I had a rough time deciding which one sounded better because they both sounded good. I concluded that there is too many variables going on: Mic position, how many feet out. Maybe I used an earlier parametric with a wider bandwidth (Q) forcing me to use another bandwidth in a different way...etc. Who knows. I settled on this approach: On the forum here you will see set the mic 8-10 feet out between the horn and the mid speaker. There are other threads that say 4-6 feet out. Maybe it depends on how powerful your system is?? For my system (which isn't anything compared to Gadget's, Dennis's & Dra's) I may have been too far out. My system just doesn't have the Balls that their systems have so I moved the mic in to 5 foot (same height position) and re-did the whole session. I think it worked really well. The indoor method was Gadget's way of trying to stay warm in Minnesota with it 30 below outside. He had to come up with something and it actually works really well. Keep at it Noize -- this is good stuff! Anyone else have any specifics to their flattening session? How far out? Mic position?
  • DennisDennis Posts: 801
    If you are outdoors, the purpose of a 10' or 12' mic position is for the mic to see a single source of sound. The closer you get to a two way speaker cabinet, the more noticeable the two sources become and it becomes more difficult to center a mic on those two sources. Now, as soon as you take it indoors, the reflections will cause you to rethink mic position. The only indoor stuff I personally do is tuning the system to the room, and reflections are just an unavoidable evil.

    Here's a link to Mikey's paper http://www.dbxpro.com/Forum/viewtopic.php?t=957

  • GadgetGadget Posts: 4,915
    How many more \"variables\" can be added to the mix is nearly infinite... in the case of the average site user...the possibilities are endless.. and daunting... In the case of those of you that can see beyond the basics we preach here will have to be more resourceful...this is where we employ all the knowledge we have acquired and seek out those that are on a plane above ours to see what they do...There is a wealth of info and opinions on what works best... the truth is ... the ONLY best thing ... is that which is best to YOU...because if you don't like the way it sounds...

    Sound is subjective.. I have said, and I will again \"What is my nirvana could be your crap! :shock: Remember that BE's of the 70's-80's had a significantly different sound \"expectation\", and equipment to work with...Back then... I actually started out with a tube Bogen mixer amp, and Shure column speakers...Slapback echo was a reflection off the back wall of the gym...
    So, I have always postulated that with power comes responsibility... :idea: and with both comes expectation... the expectation that you will suck it up and learn all that is necessary for you to grasp the concepts and techniques that are used to complete whatever level you are on...

    Here's the unfortunate thing..
    :arrow: \"The more you learn... the less you know\" :idea:

    this is a universal truism...\" Ignorance... \"may\" be bliss, but it sure won't help put on a show...

    The techniques here are designed to stimulate your mind...IF you really cared THAT much about what you do you'd be using SMAART, or some other FFT based measurement system to set your sound... Surely you have gathered at this point that an RTA based measurement system is flawed at it's design.. It ONLY measures frequency/volume per band equalization...and that's only 28 \"ISO\" frequencies... what happens between those \"bands\"?

    If you are an experienced user, and you have a brain, use the techniques and tips to come up with your 'OWN' best sound... I have said all along that you should LEARN... and LISTEN... and implement what you have learned to make changes...We are but a conduit for you to discover your potential...

    Be all that you can be... then... GIVE IT BACK....I have...


    When your applying PEQ\"s for GEQ (Auto EQ)setups, use broad strokes as opposed to narrow PEQ hits... Don't worry about the small problems within the \"broader\" GEQ plots, use 'Q' parameters closer to 1.0 than 3.0 - 4.0 always take into consideration that isf it sounds like CRAP ... it IS CRAP!
  • DennisDennis Posts: 801
    The Shure column speakers originally came with a 6 channel Shure head and the whole package was called the Shure Vocal Master. Early attempt at a line array. Back in the day, a band I worked with had two of them. Sorry...went off topic.

  • GadgetGadget Posts: 4,915
    \" assuming it was a \"package\"...It was later found in a local community college in the \"theater\" with a TEAC mixer, and the latest 100 watt Crown amps... :idea:
  • I thank the forum gods for all their guidance and wisdom!!!

    As I said before my system, small as it is, sounds fantastic!!! There is more definition, even in the monitors. I will strive to learn more and experiment more. I can't wait for our next gig to see how the band sounds.

    Thanks again guys
  • Well I did a DJ gig in a school gym. My system sounds great, but is slightly under powered for such a large area. (That's an understatement)
    The subs are ok, but the mains need some work. I think I'm running them way under powered.

    Speakers are:
    Peavey TLS-5 Speakers
    Power - 150 watts continuous, 300 watts program, 600 watts peak
    Frequency response - 60 Hz to 17 KHz (+/-)3dB
    Impedance - 8 ohms
    Crossover frequency - 1800 Hz

    Power Amp is:
    Peavey PV-900 Power Amp
    180watts/channel @ 8ohms
    300watts/channel @ 4ohms
    600watts/channel @ 8ohms Bridged
    I'm currently running the TLS-5's from channel A, Channel B is running monitors

    I want to run the PV-900 in Bridge mode to the TLS-5's. The PV-900 manual talks about running a 4ohm load in bridge mode, but does not list the output power in the spec. sheet.

    :?: Questions:
    1. Will running the amp in bridge mode give me any more... db's, loudness, volume... (you know what I mean)
    2. Is this a safe thing to try, safe for the amp and/or the speakers, where the spec sheet does not list a rating for a 4ohm load?

    Just trying to get all I can out of what I own, but if this works I'll still need to get another amp for the monitors.

  • DennisDennis Posts: 801
    According to the PV900 manual available on the Peavey website:

    4 Ohm EIA 1kHz 1% THD 900W RMS
    8 Ohm EIA 1kHz 0.1% THD 600W RMS

    The following is a short explanation of the EIA standard and was stolen off the internet without the owners permission:

    Thankfully, there are two common standards that make it easier to compare amplifier output ratings: FTC and EIA. The FTC standard, established by the Federal Trade Commission, requires a manufacturer’s stated power rating must be met, with both channels driven, over the advertised frequency range – usually 20 Hz to 20 kHz – at no more than the rated total harmonic distortion (or THD).

    The EIA rating, established by The Electronic Industries Association, reflects the power output for a single channel driven at mid-band – typically 1 kHz – with 1% THD clipping. This standard inflates the amplifier’s power points to 10 to 20% higher than the FTC ratings.

    Of the two, the FTC rating tells you much more about the product than the EIA rating. The FTC rating gives you the average power output for both channels over a wide frequency range and lower distortion level. This is a much more conservative – and realistic – measure of an amplifier’s average output power. But in order to claim more power, some manufacturers might list only the EIA numbers; others will disclose both FTC and EIA output ratings enabling you to easily compare manufacturer’s specs.

  • I have the PV-900 manual, but could not find the 4ohm bridge rating. I assumed it was 900, but I did not want to assume :oops:

    Dennis, thanks for the tip on the ratings differences. (EIA vs. FTC). I would still like opinions on my questions:
    1. Will running the amp in bridge mode give me any more... db's, loudness, volume... (you know what I mean)
    2. Is this a safe thing to try, safe for the amp and/or the speakers, where the spec sheet does not list a rating for a 4ohm load?
    I also read on a vendors site that its not recommended to run this amp at less than 8ohms in bridge mode, could that be true? The manual just says the amp will run cooler at 8ohms in bridge mode.
  • GadgetGadget Posts: 4,915
    If the amp offers a bridged rating it is usually OK to do it.. HOWEVER...
    1. Bridging is harder on the amp (it works harder)
    2. It draws more current, so if the supply is questionable....don't
    3. The amp will run hotter

    Know this... in order to get twice as loud you need 10 times the power :shock: :shock:

    Yes you will realize more volume but it won't be a huge change...If the subs are adequate raise the xover point of the tops and you will get more out of them since bass draws more current the lower the frequency.

    Does that answer your question?
    :?: :?:
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