Which QSC Amp? I've Got 3!

Zooberwerx · #1 10-04-2009, 12:52 PM

Here's the deal: I'm currently using 2 QSC RMX 1450's (both in bridged mono / 1400 watts @ 4 ohms) to power:

(2) Carvin LS1503's - 400 program / 800 peak / 8 ohms

(2) Yorkville 18" Subs - 300 watt rating / 8 ohms

I also have a really nice QSC PLX 3102 amp (600 watts into 8 ohms stereo and 3100 watts into 4 ohms bridged mono). Would there be any logic in swapping out the main's RMX 1450 for the PLX 3102 or do I have things pretty well matched? I was toying with the idea of going stereo but I'm not sure if 600 watts / channel will be sufficient.

As always, I appreciate your collective insight!

Riis

TimmyP · #2 10-05-2009, 02:14 AM

700W/box is a bit much for a box rated 400 Program - the rule of thumb says 400W. I'd use the PLX in stereo. It's only a little less power than the bridged RMX, but it will draw less juice from the mains (and it's less weight to haul around).

Zooberwerx · #3 10-05-2009, 05:54 AM

Quote:

Originally Posted by TimmyP

700W/box is a bit much for a box rated 400 Program - the rule of thumb says 400W. I'd use the PLX in stereo. It's only a little less power than the bridged RMX, but it will draw less juice from the mains (and it's less weight to haul around).

I'll give it a try. I believe the PLX is a more efficient design as well.

Riis

JackANSI · #4 10-05-2009, 12:26 PM

I'd put the PLX powering the 1503's and the RMX's powering the subs. Aside from power you also have to consider sonic quality. I think the PLX trumps the RMX in that arena pretty easily. Could also biamp the 1503's with the PLX on the mid & hi, an RMX on the low, and an RMX on the subs (if your crossover supports 3-way that is)

And unless you're going to use the pan knob on your board, or record off it, just keep it mono.

Zooberwerx · #5 10-05-2009, 07:24 PM

Quote:

Originally Posted by JackANSI

I'd put the PLX powering the 1503's and the RMX's powering the subs. Aside from power you also have to consider sonic quality. I think the PLX trumps the RMX in that arena pretty easily. Could also biamp the 1503's with the PLX on the mid & hi, an RMX on the low, and an RMX on the subs (if your crossover supports 3-way that is)

And unless you're going to use the pan knob on your board, or record off it, just keep it mono.

Kinda what I was thinking. Now, what should I do with regards to configuration? Should I run both the PLX and RMX in stereo (one side per cab) or go with bridged mono on both? Note: I'm very careful with volumes and the attenuators. Really need to plot things as I'm ready to install a dbx DriveRack.

Riis

JackANSI · #6 10-06-2009, 10:07 AM

I use a similar setup for smaller gigs, two LSx1503's and two LS1801N subs. I run the tops in biamped stereo and the subs in bridged mono.