Technical question...

[Killjingle]

http://www.musiciansfriend.com/product/ ... sku=601224

http://www.musiciansfriend.com/product/ ... sku=481565

To get the most out of these enclosures, would you run these stereo or mono bridged? I know the wiring has to be changed and all that jazz; this is all the power and speaker I have to work with.

Also to grab some discernable thump, would you stand these speakers or let them sit on their sides? The room is mostly wooden,drywall 4' and up; seats about 500, and has suspended ceilings about 12 ft high. We will add on to this system sooner than later, but for the short term this is what we have to work with on the lowend. Keep in mind I did not even bother mentioning the topend of the PA, and we are most def running a crossover, and the mids and top end sounds really decent. I am looking to grab a few decibels out of the lowend, and maybe push a little air. To my surprise this lower half of the PA is doing a DECENT job, and I am impressed enough with the speakers that I would consider adding another set with a slightly diff power setup.

Thanks in advance...

[bassist_25]

This website may give you an idea of what to do with impedance and power ratings to help maximize your available output.

http://www.aqdi.com/speakerz.htm

[lonewolf]

Those are 4 ohm cabinets, so you should not use that power amp bridged with both cabinets in parallel because its not rated to operate at 2ohms bridged. Rewiring them can result in an 8 ohm load when bridged which will work fine, but won't maximize the power on the amp. Either way, you will get about 750W per cabinet. That's a little over half the cab's rated power. Not a good idea.

Basically, that amp is grossly underpowered to push both cabinets.

By rule of thumb, you should get an amp that is 2x the rated rms power of the cabinet. In this case, you would need a RMX2450 amp bridged on each cabinet.

That cabinet is designed to be laid widthwise flat on the floor so both speakers use the floor in the half-space condition to get an extra 3db output. Also, there is acoustic coupling between the drivers that should result in another extra 3db output. This coupling works better when both speakers are under the same condition, which can only happen if they are both parallel to the floor. The advantage to standing them up vertically is that you would get a longer throw.

[songsmith]

Yep, lonewolf's right on the money. There's a local church running these (!) and they fry the drivers a few times a year with a low powered amp. A clipped amp send nasty distortion to the drivers... which is deadly to both speaker and amp. An overdriven input sounds like crap, and an overdriven output breaks crap.---------->JMS

[lonewolf]

To answer your 1st question about mono vs. stereo on subs. I like to use a mono summed signal for the subs. Subwoofer frequencies are essentially omnidirectional and stereo separation is virtually nonexistant, so you don't gain anything by going stereo.

On the other hand, if you run the same signal everywhere, it gets reinforced everywhere, resulting in a denser (for lack of a better word) sound.

[onegunguitar]

What would we do without Lonewolf-the man knows his electronics!!!!

[Killjingle]

thanks for the tips;

I figured standing them would help improve the throw, but I was concerned about the loss of bass impact. I am going to speak to the guy in charge and discuss the importance of bringing another power amp into the conversation. There is no doubt that there is no less expensive way of doing shit right; but I was hung up on the ohmage of the cabs. Its somewhat suprising that the power amp doesnt clip more than it does. The last show seemed to aggravate it a little, and I want to help him protect his investment.

Thanks...

[bassist_25]

The QSC RMXs are tanks. I have an RMX850 that has had stuff done to it that would have blown up other amps; some of it was my own dumb fault and some of it I coudn't help. They're a great value, and IMO, it blows away the Crown I had that was of similar design. I've since racked a lighter (though I still hate picking up my rack) and more powerful amp from QSC's PLX series, but the RMX gets pulled out anytime we run our own vocal PA.

[lonewolf]

What would we do without Lonewolf-the man knows his electronics!!!!

[Killjingle]

I appreciate youtr reply Lonewolf; it helped us make an informed decision.

Its not a perfect world; but we are gonna monobridge one side with a QSC 2450 and the other with a Europower 2500....

I am one of those guys who learns all kinds of info, asks 10 million questions, but if I dont use the information I learned within 6 mos I tend to forget everything I learned. I should have known that these things were severely underpowered; but I try to get my feet wet in too many directions. I wish we had matching poweramps on the subs; but we are outta budget for now...

I just picked up a sm57-52 mic pack that I think will dramatically help the sound out as well, and another compressor;

see my other post on a external fx unit...


THANKS again

[stratobastard27]

Ahh, the sweet, sweet, grossly underrated EuroPower 2500. KJ, I think you'll be fine with that amp. They review like total shite, and everyone will laugh at you. Anytime I'm setting up, and other muso's are around, I catch them chuckling to themselves about my EP25. Or they outright ask me why I'd ever buy such a piece of shite. Then I'll finish wiring the PA, and crank up the MP3. Jaws hit the floor. I love this amp. I'm using it in parallel mode to run a mono sub mix into two 400w 8ohm Black Widows. Yeah, that's right guys. 450 watts to each sub. I consistently get compliments from the crowd for how good everything sounds. I'm sorry, but I firmly believe you DO NOT need 3000 watts on the subs to move some air. Depending on which freq you set the x-over, you can route things so that pretty much only the kick drum and low E or B of the bass are getting to the subs. Then, you don't need to waste sub power on freq's that don't need amplified at that level. It's all at the board!

[boot-man]

Ahh, the sweet, sweet, grossly underrated EuroPower 2500. KJ, I think you'll be fine with that amp. They review like total shite, and everyone will laugh at you. Anytime I'm setting up, and other muso's are around, I catch them chuckling to themselves about my EP25. Or they outright ask me why I'd ever buy such a piece of shite. Then I'll finish wiring the PA, and crank up the MP3. Jaws hit the floor. I love this amp. I'm using it in parallel mode to run a mono sub mix into two 400w 8ohm Black Widows. Yeah, that's right guys. 450 watts to each sub. I consistently get compliments from the crowd for how good everything sounds. I'm sorry, but I firmly believe you DO NOT need 3000 watts on the subs to move some air. Depending on which freq you set the x-over, you can route things so that pretty much only the kick drum and low E or B of the bass are getting to the subs. Then, you don't need to waste sub power on freq's that don't need amplified at that level. It's all at the board!

how true how true. i run 4ep2500's on my rig and i never have had a problem. i've had them for 2 years now and are still dependable.

[Killjingle]

I am actually very tickled with the performance of the EP 2500. It has done everything I have asked, and I am thinking about adding a few more.

[LHSL]

http://www.musiciansfriend.com/product/ ... sku=601224

http://www.musiciansfriend.com/product/ ... sku=481565

To get the most out of these enclosures, would you run these stereo or mono bridged? I know the wiring has to be changed and all that jazz; this is all the power and speaker I have to work with.

I think the your best solution would be one RMX4050HD in stereo 4 ohm to drive two of these cabinets. The Yams are only rated at 600 Wrms. Ideally you want to give them between 900 and 1400W each. An RMX4050HD is 1400W x 2 4 ohms. A perfect match.

A bridged 2400 is WAY to much power for these. The voice coils will not stand up to that type of abuse for long. Since there are two drivers, each is probably a 300 Wrms driver with a 2" VC. I would not put 2400W into one of these with rock program. Jazz, or something a little lighter, you might do ok actually.

Underpowered amps can blow compression drivers from super high frequency transients, but if a speaker cone is rated at X Watts rms, it should be able to handle any smaller amp no matter how clipped it gets until the output goes full DC on you.