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No presets!!

edited January 2007 in PA General Discussion
OK.. i bought a DRPA recently and i like the fact that it has presets for crown and jbl but my DRPA is the extent of my harmon product line... my setup includes 2 peavey sp2 daisy chained, 2 peavey sp118 daisy chained, and 2 qsc RMX 2450 each bridged. i currently don't have the rta mic and was looking for some help with setting this thing up (geq/peq crossovers and such) i'm a mobile dj and move around to many venues, do indoor and outdoor gigs, and sometimes just use the setup for things like award banquets with no music. any help is much appreciated.



  • GadgetGadget Posts: 4,915
    So your doing DJ work in MONO? Hmmm...thats odd... As for the setup, I would set up (for indoors) an HPF of 45 hz (50 outdoors) using a BW18 filter. I would set up an LR 24 @ 100 hz LPF and a 100 hz HPF for the tops, again at 100 hz and LR24. ABSOLUTELY NO compression... you can set the limiters but do a search on the former forum home (above) and read the \"tutorials\" and \"user submitted white papers \" for additional information and suggestions..

    I'd suggest a 2x3 or 2x4 setup (you should set the RMX up as bridged and go 2x3 with mono subs if you haven't already)
    thanks for the reply...yeah i know it is odd to run mono but power hungry speakers and expensive amps come into play... i plan on purchasing 2 more 2450 along with 2- sp 4 dual 15\" and 2- sp218 dual 18 \" that way i run each amp mono pushing each individual cab making it stereo. by the way, where can i use the rta mic to set the GEQ of the system when i go to many venues?? i know i can save each venue but i don't hit one spot alot times in a row. can i do it at any venue or is it best to do it outdoors??

    thanks again
  • GadgetGadget Posts: 4,915
    Craig I understand completely.. perhaps you might want to consider the Yamaha P7000 series amps that only weigh 28 lbs and If you go to Full compass they are only a few dollars more, or go to the Crown XTI 4000 that is around $800 and both have more power are more efficient, and are great amps...

    As for the RTA mic thing... OOFDA thats a really tough call... unless you know what your doing you can do more BAD than good with one...You see, the Auto EQ tend to do the exact opposite of what its supposed to... As an example lets see what happens if you place a mic on a stand in a reflective room.. Now lets look at the room having a 10 foot ceiling and a 50 X50 dimension.. a very common size. @ 5 feet the first reflection of roughly 50 hz will cancel at the mic Now the DRPA will not hear the 50 hz and will boost it up till it is most likely obnoxious.. this usually only happens in the upper frequencies though. In most cases you will find that room modes will cause broad LF smashing by the Auto EQ. This is because a mode sets up, a mode happens when a LF wave hits a boundary, and bounces back and meets an oncoming wave and they couple to increase that frequencies volume... if you place a mic in this spot this frequency will be drastically cut by the DRPA.

    Likewise if you have a mic in a specific location and a wave of a particular frequency arrives out of phase by 180 degrees the wave will cancel... move a few inches and that frequency no longer is a factor but another takes its place.. or multiples given multiple arrival times...

    This is further exacerbated when you put two speaker stacks in the mix.. now we have multiple paths...Besides, using a GEQ to equalize a speaker system within a room has been compared to carpet bombing when a sniper rifle would do...Remember, you can't equalize a room... that would require a bulldozer...you would be far better off to use better speaker placement than equalize out the effects of these reflections.. try and get the energy on the people and off the reflective surfaces... Further try and have a system that is nearly flat, this will keep unwanted energy from becoming destructive in the room...


    The above is are charts provided by one of our contributors that helps demonstrate just some of the modes and reflections that plague this business..

    You could take multiple measurements and attempt to extrapolate the data with some sort of spreadsheet, but if you truly want to get into this more accurately you will need to get an FFT based measurement that takes into consideration much more than just energy levels of a given frequency within a reverberant space...
    Be well
    welll. i'm real big on the way my equipment sounds and was wondering if i can get some pointers with the GEQ or PEQ since it is not a good idea to use the rta mic. also i'm having a problem with not being able to get alot of volume out of my microphone when i have my music playing... it causes the the mixer to clip. the music portion never causes the mixer to clip but when i speak into the mic it causes it to clip and on top of that i can barely here myself over the music. my mixer is a denon dnx-400... i also know that i'm getting a strong signal from my mic receiver to my mixer.

    if you have any idea of what it could be, any advice would be helpful even if it is because that mixer isn't the best for audio and vocal.

    just to make sure everything is understood, i'm using

    2- peavey sp2 link: http://www.peavey.com/products/browse.c ... P%AE+2.cfm

    Subs 2- peavey sp118 link: http://www.peavey.com/products/browse.c ... AE+118.cfm

    Amps 2- qsc rmx 2450 link: http://www.qscaudio.com/products/amps/rmx/rmx.htm

    mixer- denon dnx 400 link: http://www.denondj.com/prodview_item.as ... 0&x=25&y=3

    mic- audio-technica atw 2120 link: http://www.audio-technica.com/cms/wls_s ... index.html

    once again thanks
  • GadgetGadget Posts: 4,915
    Have you ever tried adjusting the system so that the mic sounds good and worry about the music from there? Those things should tear your head off...I have an older model and I use the same amp and we use them for competitions at the Ski hill and you can clearly hear them 1/2 mile away and farther...The voice quality is awesome...and I'm using an el-cheapo Gemini DJ mixer and a Nady uhf wireless with a 58 capsule... Have you done a gain structure yet? If not the procedure is in the back of the manual, and will make a BIG difference in your sound. Also follow the link above to the \"former Forum home\" and read through the stuff in \"tutorials\" and User submitted white papers...

    What have you set the system crossover up at? I'd suggest 90-100 hz with that setup, but you could go as low as 75 hz if you wanted, but then more power is required...Try that and let me know what happems..
    i have done the gain structure and i set my crossover at 90 hz. i'll try setting my mic up first this weekend like you said... what about running the button next to the left input of the drpa at +4 instead of -10? is it ok or should i just leave it alone??

  • GadgetGadget Posts: 4,915
    Your mixer is +4.. that is where it should be. Remember that the output volume controls on the DRPA ARE the xover gain controls...That xtra umph from the +4 input will mean you need to re-do the gain structure...
    geez i'm ruff with this stuff. i did the tutorial and double checked everything with dbx techs while setting it up and it works wonderfully. i understand it much better thanks to the dbx techs and the all mighty gadget. the outcome was that my mixer is a +4 mixer, but the gains on each channel being used must be turned up 3/4 of the way and the master must be all the way up to even get the DRPA to come close to cliping... i really notice the volume difference when using my mic. the system has more volume and way more head room. woohoo. now...i find it very easy to setup vehicle GEQ by listening to it, but it usaually has 7 bands worth or eq not 31. any pointers or just use my ears?? i think the treble is a little \"hot\" but i can't figure out what frequency... which would fit my system better GEQ or PEQ? is it personal prefrence? any pointers or just use my ears??

    hopefully this is the final time, thanks
  • GadgetGadget Posts: 4,915
    Ok so we got your vocals up to snuff and you have HF splatter.. after looking at the frequency response there is a 5 DB peak in the 9-10k range, and there is a good chance that the 3-5 k range is also at fault.

    I get the impression that you have not read this...
    http://www.driverack.com/drug/view_thre ... d_id=41419

    yet... I further presume that you don't know what a PEQ is... If you want to find the offending HF frequencies you should....
    1. select a peq, bell curve
    2. set a Q of about 3-4( fairly narrow bell) (.24 would be a VERY LARGE bell)
    3. use a negative 6-8 db (thats a cut)
    4. sweep from 800 hz through to 12k
    As the offending frequencies are swept over you will notice a decrease in their volume.. when you find the center frequency you can adjust the Q and the db of cut till your satisfied with the sound.. if you find others use another PEQ and do the same thing..You will also find that if you go to the above address you will find other suggestions...

    *Note* a peq is like using a sniper rifle to do a job that you were using carpet bombing to accomplish! (the carpet bombing is the GEQ!)

    BTW just a point of fact the DRPA has 28 bands... Use PEQ's as much as possible and GEQ's sparingly...

    Keep us informed...
    excellent easy enough. i'll give it a try and see what happens! just needed a lilttle bit of direction (or alot depending on who you ask...) i'll keep you posted.

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