Amp Power Question

remov1

I have had a Driverack PA+ for a while and have had great success over the last year or so getting a good sound for our 5 piece rock band.

I have to clarify up front that I am not a sound guy, I'm a guitar player that out of neccessity has had to become smart on running a PA so my experience running sound is limited. I have read the "read this first" and faq material and keep an eye on the forum for tips and recommendations.

I understand recommended power amp for live sound is 2-4 times program and for DJs the recommendation is not to go above program. I recently replaced our JBL JRX115s with PRX 415s and changed the amp setup so that I am running them in mono at 1000w per speaker. The speakers have a programm rating of 600w. This well below the recommendation for live sound but we do play dance music over the system during breaks and 1000w is above the 600 program for the PRXs.

Should I be concerned? Is there something I should do while playing music to ensure I don't damage the mains.

I'm running a cd player mono through a y cord into the mackie board through the L tape in rca jack and controling the level with the tape level control. Meter range on the board is always in the green, in the 4-7db range at max, and just bumping the bottom of the Driverack High Threshold Meter. Level on the Driverack Headroom meter in the low to mid range. Last night was the first night we've used the PRXs and new amp configuration and after some tweaking it all sounded fine but I definitely don't want to damage the new mains.

Also a quick question on the Driverack Low Threshold meter. Watching the meters while playing music with the settings I described above the low threshold meter stays in the lower third range most of the time but on heavey bass hits the the red clip light comes on periodically. The board level is fine and I checked the meter on the Crown XTI 4000 and it's fine, running no more than about halfway with no clipping and the sound is fine, no distortion. I tried decreasing the low crossover gain to get the signal down so the clip light never comes on but it really takes the thump out of the sub. Does periodic illumination of the PA low clip light indicate a problem if the sound is good?

Thanks

My setup is as follows:
Mackie CFX20 MKII mixer
JBL PRX415 Mains
Sonetic Labs SA650 Amp(Same as QSC USA 1300) running bridged mono 2000 watts into 4 ohms, 1000 watts per speaker
DBX Driverack+ running both tops and subs in mono
Crossover settings are 100hz LR24 for the xover from tops to subs and 40hz BW18 HPF on the subs
JBL SRX728 sub
Crown XTI4000 amp running bridged mono

Gadget

Also a quick question on the Driverack Low Threshold meter. Watching the meters while playing music with the settings I described above the low threshold meter stays in the lower third range most of the time but on heavey bass hits the the red clip light comes on periodically. The board level is fine and I checked the meter on the Crown XTI 4000 and it's fine, running no more than about halfway with no clipping and the sound is fine, no distortion. I tried decreasing the low crossover gain to get the signal down so the clip light never comes on but it really takes the thump out of the sub. Does periodic illumination of the PA low clip light indicate a problem if the sound is good?

Are you certain that the lights are not the compressor? Try turning off the compressor and limiter and see what happens on the LF outs.

Typically the break music is not as loud, or dynamic as the live stuff, so you should be ok as long as the comps and limiters are not meant to "protect" the system.

remov1

I just created the preset last night prior to a gig and the compressor and limiter should both be off, I'll check when I get to the club tonight just to be sure. Those are both features I haven't used yet on any of the programs I've created. Maybe something I'll need to take a look at in the future but I've read a number of opinions about both sucking the life out of your mix so I've avoided using them to this point.

Thanks for the help

Gadget

If you use a preset you could end up with the compressor set..

If not, and it's the inputs that are going red lower the gain to the Driverack and raise the crossover gains..unless they are clipping to, but I have not seen either happen in all my years, it should take +22 dBu to clip the input of the driverack...

remov1

You hit it on the head Gadget. Limiter was on on the Low side and that was wahat was causing the clip light to come on. I grabbed a preset and modded it for my equiment and didn't run all the way through it. Thanks for the tip.