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kipperj
05-09-2012, 06:50 PM
So I'm starting to think that me purchasing an IPR 3000 (440W X 2) to power 2 PV115 cabs (400W PROGRAM) was not a good idea. I've read things that say that I should double the RMS of the speakers, and others that tell me to match them exactly. From what I can see, RMS is typically 1/2 the program handling. Will I be okay running my amp at full power? I'll eventually be replacing my speakers but for now, I need to make the best of what I have. What do you think? Thanks in advance.

jayhwk
05-09-2012, 07:00 PM
Read this: http://www.electrovoice.com/downloadfile.php?i=2320

It's the best document I've read on power handling.

sss18734
05-09-2012, 07:12 PM
I used a pair of Peavey PV 215's in college for a few years and gave them 600RMS each. 440RMS for the single woofer version is a good match - just don't overdo it on the low end.

That's a nice summary, jayhwk. Good post.

kipperj
05-09-2012, 08:16 PM
I'll be using my crossover to help with the low end. I appreciate the help, guys. The EV lit was very helpful.

jayhwk
05-09-2012, 10:08 PM
I also wouldn't believe what amplifier manufacturers say, since they're trying to sell you an amp and bigger ones cost more - the QSC amp calculator is known for coming in a bit high.

kipperj
05-09-2012, 10:58 PM
Thanks for the heads up! I can't wait to see how this sounds. I've only heard good things about the IPRs.

sss18734
05-10-2012, 12:50 AM
Let us know how it holds up. I'm really wanting to get my hands on a few of those IPR-7500's... if they ever come out...

Incognito
05-10-2012, 06:12 AM
I also wouldn't believe what amplifier manufacturers say, since they're trying to sell you an amp and bigger ones cost more - the QSC amp calculator is known for coming in a bit high.

QSC goes by the program rating or 2x RMS (though 1.5 RMS will also work) which is standard practice (for tops) but yes as long as you deliver the rated RMS rating of the speaker & keep out of the red you'll be fine.

kipperj
05-10-2012, 04:44 PM
Question about this, since I already mentioned the crossover.. I set up my cabs today. Set the switch on the IPR to thru and used the high out on the crossover, which was set to 125+hz (just to start). I got absolutely NO low end. I didn't want much, but I feel like something's off. Am I good to go? Or do you think I should check over everything. I'm sorry I can't explain it better. It's mostly highs, but absolutely no lows.

jayhwk
05-10-2012, 04:58 PM
Are you just using the PV115s, or do you have a subwoofer?

The "high out" of a crossover set to 125Hz means that you are cutting all the sound below 125 Hz. If you have a subwoofer, you would send the "low out" signal to the subwoofer amplifier, which would be all the sound below 125 Hz. You want to do that so the PV115s don't reproduce the same frequencies as the subwoofer.

Play around with the PV115s (at a low leve)l and the crossover - try changing the knob when it's playing music. Then plug the 115s into the "low out" and see what it sounds like. You should be able to hear what is happening pretty quick.

Mrspyaman
05-10-2012, 04:59 PM
use the low for the low end or lower you crossover to 80 or 100 hz. but if you are using your crossover just to filter out sub freq. just find a 31 band eq to create a controlled taper.

jayhwk
05-10-2012, 05:07 PM
just find a 31 band eq to create a controlled taper.

I have been guilty of doing this when I really, really needed a crossover, but it's not a good idea in the long term - the resulting frequency and phase response is really nasty. Basically, it will degrade the quality of your sound as opposed to using a crossover, which is designed to have a nice, smooth slope.

kipperj
05-10-2012, 07:06 PM
Are you just using the PV115s, or do you have a subwoofer?

The "high out" of a crossover set to 125Hz means that you are cutting all the sound below 125 Hz. If you have a subwoofer, you would send the "low out" signal to the subwoofer amplifier, which would be all the sound below 125 Hz. You want to do that so the PV115s don't reproduce the same frequencies as the subwoofer.

Play around with the PV115s (at a low leve)l and the crossover - try changing the knob when it's playing music. Then plug the 115s into the "low out" and see what it sounds like. You should be able to hear what is happening pretty quick.

I have two separate amps for subs. I haven't had time for that yet. I was just wondering how low the frequencies coming out of my 115s should be. Even when I set it all the way down to 100hz most of the frequencies are pretty high (no bass at all). 100hz is pretty low, isn't it? There are also high and low level knobs on the crossover. should I set them the whole way up and leave the gain at 0 to get the best signal? Yes, I read the manual. It doesn't specify. It just says to turn them up to match tonality. I was just curious how to set the high and low without clipping.

jayhwk
05-10-2012, 07:14 PM
You will notice a pretty drastic reduction. Look for an online sine wave generator and listen to it on headphones. If you know anything about a piano, the lowest note's fundamental is 27.5 Hz and 100 Hz is two G's below middle C.

I would start with the levels set at zero, but if you notice that you have too much bass, reduce the gain of the low passband. If you want more bass, increase the gain. You'll notice clipping at your amplifiers if your gain structure is correct. Unless you really crank one of the passbands (which means something is wrong) it probably won't effect the clipping behavior of your system.

windspeed36
05-10-2012, 07:15 PM
I have mine set around 110hz. Never cross at 80hz due to it being smack bang in the middle of your kick drum range

GaFFLe
05-10-2012, 08:18 PM
Read this: http://www.electrovoice.com/downloadfile.php?i=2320

It's the best document I've read on power handling.

Damn... that docs from 1979 and still seems very relevant.

kipperj
05-10-2012, 09:22 PM
I'll screw with it some more and check in if I have any issues. Thanks for the help!

sss18734
05-11-2012, 02:03 AM
Since you're only using your mains, just set the crossover on your IPR to "Thru." Listen to the speakers - if you notice they are distorting, turn the bass EQ on your mixer down a bit. You'll probably find you have to keep it on the low side at high volume.

kipperj
05-11-2012, 12:15 PM
All is good, guys. Everything sounds great and my speakers are finally getting enough power (and I have a little extra). Thanks for the help! Only thing is I can't use THIS crossover when I don't use my subs. Well, I could, but there will be absolutely no low end.