DRPA with Crown XTi-4000 Vs. QSC PLX 3402 for JBL SR-X Cabs

Pure Energy Productions

I'm rethinking my plan of attack with my new rack.
Here is my current system:
(6) QSC PLX 3402's
(4) JBL SR4733X's
(2) JBL SR4719X's
(1) DBX DriveRack PA
I looked at JBL's web site and they recommend using 4 Crown XTi-4000's with my system. 2 bridged to the subs and 2 stereo to the tops. This would lighten my amp rack, require less wiring and give me space for more equipment in the future. What do you guys think?
Thanks for the help!

Phil

Gadget

Not for my money... loose 3000 total watts, loose 10 lbs? sound s like loosing proposition to me! The 3402 is a proven workhourse. I have talked to may people who will never buy another Crown product. I have talked to people who have tried both, and each one thought there was no comparrison in sound quality...

Just my $.02
Gadget

Pure Energy Productions

Hey Gadget,
Thanks for the reply. I could run 4 PLX 3402's, 2 bridged for the 2 subs, 2 stereo for the 4 top's low biamp, and 2 PLX 2402's to the 4 top's hi biamp. Am I closer?
Thanks,

Phil

kenny

I think you will only need 1 amp for the highs. Woulb be a 8 ohm load for 2 16 ohm comp drivers per side. And a 1202 or 1602 might be a better choice than the 2402.

Gadget

Look, don't take my opinion.. go to your local dealer and listen to the Crowns, I know I will never buy another Crown amp. I like the Macs, but this new shit just sux in my opinion.

Otherwise, I recommend those PLX's. They sound very musical, are very robust, and not that much heavier...They are universally accepted, and I think you will find that you will be much happier with them...

Even though they are not in the presets its easy to set them up..don't let those Harmon assholes fool you, a preset is no reason to choose one amp over another... Sound quality is paramount, and I know you will like the QSC's!

Thats my $.02

Gadget

Gadget

Kenny,
Think of it this way... too much power is never enough... If you have all the amps the same and one goes ... you still have plenty of power... and universal exchange-ability...

you can always turn it down.. but when its all the way up and its not enough.. then what.. blown drivers.. thats what!

Its like when your hot and your naked.. how much more can you take off? If its cooler you can always add more cloths.. Thats only an analogy... you can always turn a too powerfull amp down, but once you run out of power the game is over... you will destroy something!

Gadget

Pure Energy Productions

Here is what I own in the PLX series to work with:
4 - 3402's
2 - 2402's
So it looks like I could power my system like this:
2 - 3402's bridged powering 1 - SR4719X each
2 - 3402's stereo powering 4 - SR4733X LF in bi-amp mode
1 or 2 - 2402's steroe powering 4 - SR4733X HF in bi-amp mode
I'm trying to do the math on the power needed vs. power rating of the PLX 2402 for 4 HF drivers of the SR4733X's. Also, do I run the subs in discrete mode?
Thanks for all the help!

Phil

kenny

Gadget wrote:

Kenny,
Think of it this way... too much power is never enough... If you have all the amps the same and one goes ... you still have plenty of power... and universal exchange-ability...

you can always turn it down.. but when its all the way up and its not enough.. then what.. blown drivers.. thats what!



Gadget

I agree with you...

I would still only use 1 amp for the comp drivers even if its a 3402
Why carry 2 if 1 will do the job...I'm old.......that 20 some extra pounds could be the end of me....

FWIW.... I run a system very similar to the 1 in question, but I run 2402's bridged LF (4719's) 3402's stereo MF and a 1202 stereo HF....seems to work well for me.


I do need to thank you Gadget....When I was interested in buying a Driverack your posts' on here made it an easy decision. DBX should toss you a 4800.....You have helped many people with problems they are having with the Driverack....Myself included.

Kenny

Pure Energy Productions

Kenny...are you using 2 subs and 4 top boxes like my system?

kenny

Pure Energy Productions wrote:

Kenny...are you using 2 subs and 4 top boxes like my system?

That is what I'll be working with this weekend......subs will be under the stage......tops will be on stage.....stage is 5 ft above ground level

kenny

Gadget

Thanks Kenny,
I try, and you are correct. I just believe in more power than less... It really makes a difference in the tightness of the bass. I agree, even the 2402 should be able to run the horns. I on the other hand run stereo... evenn if only running the effects in stereo. Its also on a lot of riders these days...I'm old too probably older than you... but an xtra 20 lbs versus low power..
I would love for them to give me one, I figure what with 4 years + and thousands of posts, plus the untold thousands of units I have sold for them its the least they could do... but they won't...

Pure energy.. the SR4733X are 4 ohms, best bet run two of the 3402's in stereo for the subs
run the other two 3402's on the mids.. bridged, and the 2402's/ or as Kenny suggested one would most likely do.. on the horns...

Not optimum power.. but.. now if you had those 6 3402's like you said in the first post...

Let us know how it works K?
gadget

Pure Energy Productions

Gadget,
Stereo on the subs? Do you mean amps bridged and 1 to each sub?
Bridged on the mids? That would be be 2 ohms!
Stereo on the 2 2402's to the Horns?

Gadget

Jeez.. I need to read more carefully.. I thought it was 4 - 4719's and two tops.. ya, and as you probably know... 2 - 4719's per 3402 would have a 4 ohm load per amp channel... since the 4719's are 4 ohms yes.. one 4719, bridged per sub. one 3402, stereo, per pair of tops, and the same for the horns...that would be 425 watts per horn... one 2402 would suffice as Kenny said, you will have 1100 watts or 525 per 15\" speaker, and and 3400 watts per sub. The mids are under powered, and are your weak point at less than 1/2 the recomended power. The 4719's are power hungry, and you are a little short for optimum performance... but it should work. I would definately consider a 4-45 hz HPF for them as usless luffing will rob power you need for performance. If you sweep through and find the best xover point I figure you would end up at a lower freq, but I recomend, since you are so limited in power on the mids, that you try 120 hz to optomize power to the mids...The Jbl site will give you all the tuning info for the tops...

Sorry for the mixup... I am quite blind at times...

Gadget

Pure Energy Productions

Thanks Gadget! So the system would look like this...?

2 - SR4719X's each powered by 1 PLX 3402 in bridge mode
4 - SR4733X in biamp mode with LF powered by 2 PLX 3402's in stereo mode, HF of the SR4733's powered by one PLX 3402 in stereo mode

My goal is to not have the system under powered. That is why I sold all my Crown MacroTech’s. I would have needed 3 more amps and 3 more available circuits to bring the system up to power specs. Too expensive and hard to find enough AC power!

FYI...I have 3 PLX 3402's in my monitor rack...maybe I could swap 2 of them for the 2 PLX 2402's I have and move the 3402's into my FOH rack for more power.

My monitor rack currently has 3 PLX 3402's powering 6 separate monitor mixes. I am using 4 MPro 412's and 2 MPro 415's. Sometimes I do have to put 2 speakers on 1 mix. Would powering the 412's with the 2402’s be O.K.?

Crap...too many options...! Basically I own enough to make all this work, but my brain is going to explode trying to figure out the best way to power everything! Based on what I currently own, what should I do?
My amp and speaker inventory for my B system is as follows...

1 - DRPA
7 - QSC PLX 3402's
2 - QSC PLX 3402's
2 - JBL SR4719X's
4 - JBL SR4733X's
4 - JBL MPro 412's (monitors)
2 - JBL MPro 415's (monitors)

Thanks to all for your valuable help!

Phil

Gadget

I think you are short on low end.. I would think that the way I set you up is still ther best way. If you had more subs, then you would probably need more power to the mids, but I figure you are going to be about right with the proposed setup. Remember this, optimally, you need 2X the power rating of the speakers. I prefer Crowns addage of 2-4 times. So with a power handling of 1200 watts for the 4733's, 2400 watts would not be unreasonable... this would then feed each driver/speaker with up to 1200 watts...that may seem like a lot, but in reality more power will help keep you from blowing up your drivers... power doesn't usually kill speakers exhausted power supplies(clipping) does... you can blow drivers way easier with 100 watts than 2000 watts... yes, a too powerfull amp can drive the speaker against its mechanical stops and destroy them that way, but believe me they would be making a terrible clacking sound... unmisstakeable as bad news.. clipping is a nefarious silent killer... once that lets the smoke out... its really hard to get it back in. chuckle

Try what I gave you ... the only other option is a couple more 2402's and 1 per top and 1200 watts per speaker/driver. if you get more subs then we will have to reconfigure.. till then I think you'll be ok
Gadget

Pure Energy Productions

How about just running 6 PLX 3402's bridged, 1 to each speaker and not biamping the tops?

Pure Energy Productions

I got the system hooked-up and the DRPA programed through the Wizzard. System sounds good, but how do I use the JBL speaker tunings I got from their website? It seems like the LF on the 4733's is crossed over so low I get zero vocals out of them. Is this right? HF seems to sound good and the subs kick nicely.
Thanks,

Phil

kenny

I have no user time with a DRIVERACKPA but if those boxes are listed in the wizard the tunings should already be loaded. I used driveware to load your set-up and see the hi-mid looks like it's crossed around 1200 and mid-lo around 100. You should have vocals in the mids. How is your gain structure? I read somewhere your running a GL2200..... You have some nice toys, have you thought about upgrading to a DRIVERACK 260 ? I can't imagine not being able to use a laptop to control the DSP.
[/img]

Pure Energy Productions

Gadget,
I used the set-up wizard to input my JBL speaker tunings and hooked-up everything the way you said...system sounds lame! The LF on the top cabs have no vocals...mostly muddy! I have the tuning from JBLs website but have no idea how to manipulate the settings. Can you help? I might need a step by step lesson!
Thanks A Bunch,

Phil

Gadget

Phil
Yo need to get the total system configuration the way it is now.. as I read back there was some switching around of amps? what is the config now? are you running the tops bi-amp? If you want you can call me @ 218-999-7100 and we can discuss it easier than all this typing... The tunings from JBL are just PEQ's and delay settings.. and sometimes polarity shifts.
Gadget

Pure Energy Productions

Gadget,
Thanks for the phone conversation....it really helped!

Phil