Need help interfacing live sound speakers with my power amps!

[tedr]

I have four full range cabs (JBL JRX125) and 4 subs (18" Emminence drivers in home built boxes). In addition, I have four QSC GX5 amps.

Is there a problem with having an "mismatched" load on the two channels of the amps? By "mismatched", I mean feeding a HPF'ed full range signal (out of a xover) to one channel of an amp for one JRX125, and feeding a LPF'ed signal to the other channel for a single sub thus pairing an amp with a JRX125 and a sub. I would expect that the demand on each of those two channels to be quite different. Is this a problem? A much greater load on channel A vs. channel B?

FYI, I'm thinking in these terms as I hope it would provide the least use of long speaker cables along with the convenience of running line level signals to what I envision as two amp racks, one on either side of the stage. If there is no problem with this mismatch in power demands, then I also gain some amount of redundancy. If one amp goes down, I lose just one JRX125/sub combination on one side of the stage.

Thoughts?

Thanks,
ted

[Barnabas]

Sounds like a great plan. I did that for many years with JBL boxes and Crest 8001 amps. The Crest amps actually had a special socket on the back of the amp that allowed you to plug in a crossover to send the lows to channel 1 and the highs to channel 2.

Don't worry about sending a different signal to the two channels. The power supply will appreciate the diversity.

This approach helped keep my system modular for small and large gigs.

I use all active boxes now.

[Enginearing]

i find it handy (and it seems logical) to keep the channels of ampracks the same as looking at them
IE
top amp = passive mid/hi Ch.A=L Ch.B=R ( are jrx passive? if not spread this accross the top two amps)
2nd amp = sub ChA=L ChB=R

3rd and 4th amps = foldback sends (1-4ch if passive or send per amp if Bi-amped)


of course it could be argued that a left amp and right amp is just as logical, though once you start getting different rated amps to power different elements it really does help to look at the rack layout the same way as the stack's "layout"...

depending on the impedances on your subs (and limitations of amps) you it might help to load up rather that spread out... have a llisten and see if you can hear the difference... some sub/amp combos seemto like be driven harder at lower impedance.

[mixedupsteve]

The GX series is already set up to do just this and it's what QSC recommends.. If you use the internal Xover then you only send 1 full range signal to the amp. The amp splits it into subs-1 and tops-2. The amps power supply then makes adjustments on the fly based on program demand.