Gain staging question

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in the list of advisors here Rick I would listen to those who have experience for more than three or four Legion events. Some good info here in this thread for sure.
 
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What I don't understand is how you can set the crossover setting on ONE amp to only affect one side. If you are coming in with a full range left and right to the amp and the setting on the amp is set for your subs, then by using the "Throught" 1/4 to the tops, you are actually sending full range to the tops. Full range will include bass which will in turn put more demands on that amplifier channel = high probability of early peaking if the speakers are being under powered.

You don't even have an Equalizer to control the side you want to control. Shortcuts to proper sound deployment will bring about problems like you are experiencing. For the kind of Gigs that you do my recommendation is that you get a two way crossover & EQ or a Driverrack plus two amps, one for tops and the other for subs. Put the damn thing in a rolling rack and ditch the friggin table.

Here's a pic of the IPR3000:
03004310_8666.jpg

In the past, I've been running tops off one side of the amp with it set to hi-pass (100hz and above). I was hanging 2, 8-ohm subs off the other side with the switch set to "subwoofer (100hz and below). I know we're only talking 840 watts coming off each channel but that's been plenty for weddings. I've had very few events that were large enough to push it even close to clipping. Now keep in mind that the way I re-patched last weekend, I'm sending 840 to each sub cabinet and 440 to each top cabinet. I did try "Boom Boom Pow" this past weekend and never saw clip at all. The only time I'm going to send full-range signal to the tops is if I'm not using subs. I've only had 1 or 2 gigs this season that had difficult load-ins where I left the subs in the van.
 
^^^Canute a lot of new amps do that now the have a high pass filter on one channel and a low pass on the other. I think they do this so that one amp handles one side (tops and sub) and the other the other side. But alas the Peavey is not set up this way it goes even further by having each channel having a separate set of filters. My Behringer does it that way...

behringer-nu3000-rear.png
 
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OK I see that the amp has individual settings for each channel, I get that. So you are running two 8 ohm speakers from one channel = Approx 4 oms output each side. What is the wattage of each speaker (Not the amp)? Did you say you were using Carvins, what Model? What is the Wattage of each sub and ohmage?

BTW Peavey Amps are not as Rugged as the QSCs and Crowns, they tend to peak faster especially when overloaded. I have an older Peavey and it does just that if I am not careful, however a slight adjustment on my Gate or a tweak on the EQ and the problem goes away.

Edit: OK I see that the subs you have is the MP418s, correct me if I am wrong.

This will require an output of 2ohms (4ohms divided by 2)and 1,200 watts (600x2) if you run them in Parallel. The Peavey gives an output of 2 ohms at 1490 watts (Remember you are not running bridged in bridged it would be 1640) so you have 290 watts as headroom for the subs.

The Tops I don't know the Model of your Carvins but you do the same Divide the ohms by 2 and multiply the watts by 2 which will give you the total ohms and watts for that channel. If it comes down to 2 ohms the Peavey will give you 1490 watts: 4 ohms will give you 840 watts. This is why I think the suspect is the amp power for the tops.

Second Edit: If you are using the two Carvin LM15 in parallel, then this will require an amp sending at least 4 ohms at about 950watts. (Each Carvin is 8ohms at 475watts)
the Peavey is giving you 4 ohms and 840 watts. you are then under powering the Carvins by -110 watts, just as I figured. Add a "hot" signal to the mix and it would surely peak the amp. So not only is it deficient it has no headroom.
 
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Yeah Rick, get your advice from drunks instead.
certain raw veggies have been known to help when a nerve has been hit. raw Nerve syndrome cured by Raw Veggies.
 
BTW Rick, you will need a more powerful amp than that Peavey IPR 3000 for the Carvin tops. Something like 600 watts per channel per side into 8ohms.
 
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