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DRPA and jbl mrx dual 18 subs

Tim EngleTim Engle Posts: 2
edited November 2007 in PA Configuration Wizard
I am using 2 jbl mrx 525 tops (stereo but pushing them with QSC 1450's each one 4 ohm bridge mono. I am pusing 2 jbl mrx dual 18 subs 4 ohm bridge mono with 2 peavey 2600's. My drpa does not have the settings for the MRX series speakers or the amps that I am using. I am using the JBL SRX settings for my crossover points and speaker config using 2 x 4 stereo. Also until YESTERDAY I didn't know about the switch on the back of the DRPA the -4 / +. I pushed it in and doubled the sound of my system. As you can tell I am new to this but feel like I have bought good equipment.
Can you make any suggestions for my system as far as the crossover points i'm using (80 -120), and the amp and speaker selection, since MY equipment is not in my system. I have read almost all of the postings and seems like nobody has my setup / with dual 18 subs. The system is used for my 70's 80's rock band. And we play mostly 300 person clubs and 500 person events.


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    GadgetGadget Posts: 4,915
    Not trying to nit pick..but...

    If you read all those posts, you didn't see ANY that indicated that there ARE NO speaker settings for passive full range speakers and there is no need for them...I know I indicated that in the Welcome read me first posts...As for full range tops crossed to subs there are too many variables (different speakers to choose from) to provide crossover specs for all different combinations. That said, I don't like crossing over @ 80hz since that is too close to the kick first harmonic(THUD) A 24-26 inch kick \"thud\" sits right around 80 hz. You have sufficient power to the tops to go below 100 hz so I would start out @ 90 or 100 hz. Use the LR 24 crossover slope and spread the subs LPF and tops HPF a few hz...93.6 or even 102.1 for the tops and 91 hz for the subs. This spread can help minimize distortion in the crossover region.

    Your not over powered for the subs though so I'd set a BW 18 @45 hz HPF.

    A little experimenting is always suggested and quite easy with the Driverack. I suspect you may find a delay of roughly 7-9 ms will tighten up the bass a bit. I have posted ways of determining the correct delay but the DRPA doesn't have a lot of delay, so simply sweeping through slowly and finding the spot the bass is best defined.. or focused will usually do.

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