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Need help setting up 260 with EAW LA325 Bi-amped and 400's

BTproductionsBTproductions Posts: 86
Hi all I recently acquired these speakers and now need to get a few things straight before I run them. I've done all the reading I've found on these and talked briefly with EAW's ASG. I'm new to runnig pro audio but have been into audio esp higher end home audio for well over a decade so I can speak the lingo and am familiar with most of it but not nessisarily had any real world experience with all of it.

I'll start off with how I intend to power everything. After reading all about EAW and how they reccomend 1.5 - 2x power with 6db headroom and reading these 325's having their crossovers fried at 600w I talked to ASG and I'm told even when Bi-amping give the mid/hi's 600-800w and the low's 1000-1200w. He said this is there only speaker that's the exception to their rule. I've been looking at Crown Xti2 series and have been told crown rates these amps EIA so here's what I'm thinking. Crown xti2002 mid/hi's Crown xti4002 lows and another 4002 bridged into 4ohms for the 2 LA400 sub cabinets. He said those 400 cabinets can take 1200-1600w each even though rated for only 500w.

So now im at a bit of a conundrum when it comes to setting up gain structures. I have tops which I'm going to amp with some headroom left and be very careful not to let them get to much and subs which I'll have ample headroom and can setup with +6db headroom like explained in "the read this first" topic. While I'll need to read that topic again and it's gonna take me some time stepping through it the first time. I do understand it and what the goal is so how differently do I go about it when I'm powered this closely to matching handling power?

Gadget I read the topic where you have some processor pre-sets that work exceptionally well! I'll be needing a copy of those Please!

My head has been spinning for a few days now trying to get all this in there while working full time and getting ready for a show on the 26th which is when I need to be ready with these so I'm getting a little angsty! I should also mention this will be a system used for only DJ's myself included so however that may affect anything keep it in mind. We play all types of electronic and the DJ's are not the type to crank on the gain and respect the sound guys eq job. That doesn't however mean all tracks come out with the same gain levels and yes it happened to me where a DJ put on a way overly gained track and shutdown my QSC PLX3602 and blew out my fr159z's woofers in the process. As you can see I've grown my system much larger and now have protection for it I just need to implement.

That's probably more than enough out of me as for taking the first step so head first I go!

Thanks -Mark


  • DennisDennis Posts: 801
    I don't have answers to all of your questions right now but I have roughly calculated one value for you.

    It's my opinion that you don't go a bit over 600W for the Mid/Highs. If you are using a Crown XTI 2002 for Mid/Highs, after doing a preliminary gain structure with the whole system, disconnect the speaker cables and connect an AC voltmeter to the XTI output connector. Set the limiter in such a way that you cannot push much past 49 Vrms....this will limit you to approximately 600W on the XTI 2002. While the 2002 is rated at 800W into 4 Ohms, it can go well beyond 800 when driven to clip.
  • GadgetGadget Posts: 4,915
    Hi Mark...

    Well...once you start the "DJ..." scenario, I have to throw up the caution flag...WHY? because I too started out doing just that and have run into far too many jockeys that have NO concept of what "That's all she's got captain"! means...

    That and the fact that current music for the most part is compressed to HELL and back...THIS poses a HUGE problem when trying to power speakers for reproduced (CD) audio... This generally (within the pro audio community) means that you DO NOT put more power to the speakers than they are rated for NO MATTER WHAT!!! and... if you think that brick wall limiters will protect your speakers >>> think again! The thing is.. if you set the limiters @ say +4 dBu...and then run the mains up against the limiters and then keep pushing... the limiters WILL hold back the peaks...BUT the average level will ramp UP and UP and the speakers will soon have damaging power coursing through the voice coils...the smoke is not far behind...

    I have been a practitioner of the school of "too much power is never enough"!... BUT, that is with proper gain structure, and LIVE music, which is far more dynamic than CD type audio and lets not even TALK about MP3 audio...

    Now, lets talk XTi amps...the good news is... they are light weight... the bad news is they are made in China and they do NOT make good LF amps...and that goes DOUBLE for sub amps...

    I just bought 2 XTi 2000's and they are on monitors in a club that mandates 95dBC weighted average over a 15 minute period...the monitors are also HPF'd @ 150 hz BW18.. and are 12" 2way Grundorf POS speakers with Celestion 1.5" voice coil woofers with 30 oz magnets (read this GIVE ME A BREAK...) and 1st order crossovers and tiny horns...so there is NO way those amps got even WARM... ever... and one lasted a whopping 3 months...and is still gone now going on a month and a half...

    So... back to you.. I'll look for that file but it's been YEARS and I have had several computers in those years...the chances I still have them is slim.. but if you were talking to EAW why didn't you get the settings from them... I have been an EAW acoustic partner and have the documentation somewhere here...but the settings should be on their web site...but that will have to wait for another time...off to bed with ye lad...

  • GadgetGadget Posts: 4,915
    Ya...what he said...

    Top 10 Ways To "TOAST" Speakers and Diaphragms

    If you go "ouch" after that last squeal, chances are so did your speakers! This one is compounded by proceeding to use the speakers after they have probably been damaged.

    Always check your speaker specs for the best crossover points.

    Most folks throw "extra watts" at the same speaker complement: add extra channels of amplification in concert with additional speakers.

    Outdoor gigs require at least 12 dB (16X power) more sound output than indoors, and as much as 20 dB (100X power!) to really do it right.

    The classic "smile" EQ curve is actually smiling at your speakers imminent demise! Keep in mind that EQs are best used for cutting, not boosting the signal. Need more highs? Reduce the bass...Need more lows? Reduce the highs.

    Excessive compression squeezes the life out of your music AND your speakers!

    Too little power, and amplifier clipping becomes the norm.

    Turn-off thumps, plugging/unplugging mics, etc. Mic stand knocked over, mic dropped...

    Improper mixer gain distribution, line signal too hot, etc.

    And failing to have the crossover parts checked for damage after abusing the speaker system that way! Let your ears be your guide. If you hear distortion from any clean inputs, damage has likely occurred.

  • Thanks! I'm glad I didn't buy the amps yet. I'm on my phone at work on break so I don't have time to go very far with this but how about some amp recommendations so I can do some looking when I get home. The guy at EAW said my 3602 would be good for the 325's bottom. I need to buy amps soon like I said the 26th is fast approaching. I'm confident once i figure out what amps to run you guys will be able to teach me the best way on how to run them. Thanks
  • Gadget here's a link to the post I read about your EAW settings file.

    It seems like you had made your own changes to the settings and came up with a better sound. I'm aware of the EAW .pdf.

    How about a Crown CTs1200 for the mid/hi's my QSC PLX3602 for the low's and for the LA400's I have no clue cause your probably gonna tell me to keep the watts lower than I was told as well.

    I should also say that the way I run usually is for max bass and alot of kill in the high's section on my eq. My eq with the fr159z's as tops looked like a ski slope from low to high and not a smile. I would rather not be heard from the back than blasting out peoples ear drums up front regardless of the room size or outside.

    Thanks for the help guys! -Mark
  • GadgetGadget Posts: 4,915
    My... how time flies....

    The thing is, you have 2, 15" Low mids and one cone hi midrange...speaker...that is only a fraction of the low mid outputs. I have the Carvin 153.. and they have a 6 inch mid and a 15" low mid, and one inch horn driver...

    Here's the thing...

    definition: beaming...
    what frequency does a 15 " cone speaker start to beam....
    Answer: typical mid/horn xover depends on the horn...output diameter...
    1" EXIT... voice coil dependent... can range from the 1700 hz area with 3" voice coils... to 3000hz with a less than 1" voice coil...
    1.5" and 2' exit drivers can range from 500 hz with a 4" voice coil to 1200-1500 hz for a 3" and lower voice coil.

    so what frequency does a 15" start to beam? as low as 800hz...

    This is why a 12" 2 way (which starts to beam closer to 1000hz) makes a MUCH better midrange speaker, but then they are limited by their LF extension...

    Thus the 3 way speaker and it's smoother midrange...were developed..

    BUT... then there were 3 crossover points and all the difficulties that go with trying to get them all to play together well...


    I do NOT have ANY EAW speakers...
    I have never HAD any EAW speakers...
    Dennis on the other hand MAY have worked with some...
    IF I offered something OTHER than EAW specs it would have been from someone with first hand experience and someone other than a newbie much less a novice... BUT I hang at the PSW, and there very well could have been a user there that has/had... developed a preset that I passed on 2+ years ago...

    I checked my documents.. and didn't see a tuning for LA 325 speakers...sorry...

  • MctwinsMctwins Posts: 113
    Now, lets talk XTi amps...the good news is... they are light weight... the bad news is they are made in China and they do NOT make good LF amps...and that goes DOUBLE for sub amps...


    I don't have any problem driving JBL subs with Crown MAI5000 :D .

    But, dbx is also made in China, right. :wink:

  • Ok I'll plug in the EAW settings thats no big deal. I know this isn't a forum to discuss off topic things like powering and amp reccomendations but I don't have time to go elsewhere and you guys obviously know the answers here and have experience with tons of different equiptment. If we could can we go back to focusing on what amps I should use so I can order them then I can get to setting up and asking driverack questions again.

    Need help here please

    Thanks -Mark
  • DraDra Posts: 3,777
    Do you have a budget?
    Do you want to go towards a light weight amp or an old school heavy design?

  • DennisDennis Posts: 801
    Gadget wrote:
    Dennis on the other hand MAY have worked with some...

    We used to have a pair of LA325 in the shop but sold them a year ago on Ebay. I always started out with factory settings and customized on a per gig basis but I never saved final settings
  • I am on a budget. The speakers I bought are all used but in mint condition I got a real steal on them. The CTs1200 I mentioned for the mid/hi's is on eBay for $5-800. There's also a CTs2000 for $500 but that's too much for the top section and for the bottom I feel like my PLX3602 would do a better job? For the LA400 subs I have run them already on my 3602 and it did fine I plan to pick up another pair of 400's then a 3602 would be giving them 1100w FTC which pretty much matches their 500w each rating but I'm open to suggestion on an amp for those. Let's say a budget of no more than $2000 buying used or discounted equiptment. Proaudiostar out of NY usually can get you a huge discount. Also besides what I can afford if you want to chime in on what the preferred amps that would give me a target to aim for in the future.

    Thanks -Mark
  • GadgetGadget Posts: 4,915
    McTwins ...your too funny...I would KILL for a bank of those amps...

    Well, the tried and true in the lower cost amps are the QSC amps in my opinion..If you have the budget I am BLOWN away bay the Power Soft/ Digam amps...

    Of course the old Crown MA amps are hard to beat for low end power

    The QSC Power Lite series are excellent as well..

    Lab Gruppen are top notch but spendy...

    Not too impressed with the Crown XLS amps.. just not enough power

    Same with the GX series by QSC and they are not bridgeable...

    same with the new amps from Peavey...(not set up for bridging) SUPER light weight... and good power, and should be considered where stereo power is right.. These things are supposed to sound incredible.. and I would put them on the highs and mids the current offerings are an 1800 watt and 3000 watt versions...

    The IPR1600 is 320 watts @ 8 ohms and can be bridged...for 600 watts @ 4 ohms
    http://www.peavey.com/products/proaudio ... B1600.html

    The IPR 3000 is 440 watts @ 8 and just under 1000 bridged...
    http://www.peavey.com/products/proaudio ... B3000.html

    I was told the larger amps are NOT bridgeable...and I do not believe the 4500 and 6000 or the DSP models are available as yet...and were promised LOOONNNGGG since...but parts availability has been... forthcoming...

    The XTi 6000 is "supposed" to be the exact same circuitry as the Itech amps with a different power supply... I have not verified this...

    just a brief note on the Powersoft/ Digam amps... we have a Digam 5000 amp. This amp has powered 6 LABsubs (thats 12, 12" drivers!!!) outdoors, and you could FEEL the low end 3/4 of a mile away! AND it was running on a 14 gauge 100 foot power cord! That SAME amp.. was put on a pair of 8" studio monitors and no matter HOW HARD they were pushed... they NEVER got hurt, or even sounded strained.. but got STUPID loud... these are INSANE power amps!

    I have even used Behringer's new EPX 3000 amps and they have held up pretty well in Disco applications...

    So... thats a brief capsule of my thoughts..

  • I found a digam Q 5000 for $1090 I'm thinking of pulling the trigger on it and using it for the LA400's. Sounds like a killer combo there. If I do that the PLX3602 is going on the 325's bottom and I still seem to like the Crown Cts1200 for the top but no thoughts on it there yet? I'm kinda shocked at the mention of peavy I always thought of them and Behringer as cheap junk but those companys seem to stumble upon a golden egg every once in awhile. I would need 2 IPR1600's bridged for the mid/hi's and that's more rack space than I have plus they don't have but a signal and ddt light which I assume is a clip light. So compared to the CTs1200 I'd have signal,-20,-10,clip and half the rack space. Cost about the same either way besides the extra rack space. Hmm thoughts?

    Thanks -Mark
  • GadgetGadget Posts: 4,915
    No the CTs amps are good as well.. I have a 3000 and it's been a workhorse..

    Peavey amps are for the most part bullet proof and have been the anchors (boat anchors though they are) of many a rig for decades... the old CS amps were real work horses...

    BTW the IPR 1600 weighs in at a whopping 7 lbs... :shock: :shock: :shock: has a 5 YEAR warranty...and a terrible blue light :mrgreen:

  • DraDra Posts: 3,777
    B'ger and Peavey should not even be mentioned in the same breathe. It is not uncommon for a PLX3602 to be used on hi's , mid's, and Low's, just for uniformity. Clean signal is the key to the life of a horn or tweeter. Obviously you may have to dial it back, but the key factor is output voltage, which will inherently be miniscual in comparison to the subs, for example.

  • Gadget you sure do seem to like those Peavy amps. I wish they had at least -10 led. I went ahead with the Digam 5000! Now it's just making a decesion on the top amp. I'll be able to fit everything in my current racks if I go with one 2 space amp so for that reason I would perfer either that Crown or another QSC PLX over the Peaveys but if there gonna sound that much better I guess one can live outside a rack for a little while. I always lean toward not sacrificing sound quality so this amp is the most important for clear highs. I'm leaning towards the Crown but I also saw it's for installed sound. Will it not like life in a mobile rack case on the road? Decessions Descessions!

    Thanks -Mark
  • DraDra Posts: 3,777
    Don't forget to check the air flow direction on the various amps.

  • Ok looked at a pic of the back panel of a CTs and noticed theres no speakon connectors. Obviously I know why they say installed sound now. I'm just gonna go with another PLX for the mid/hi's for now I'm running out of time and I just need to get on with it! I'm gonna assume the 1802 is the best option for the mid/hi's power requirements? Or the 1104 as I don't need 2ohm ability? The 1104 has input clipping of 5.5vrms (+15dbu) and the 1802 is 11vrms (+21dbu) Not real sure what that affects so which would be best given my application?

    Thanks -Mark
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