Channels and Ohms

[rv_bass]

I have three 8 ohm cabs, combined in parallel that would give me 2.67 ohms.

My amp (QSC GX7) has two channels, each can go down to 4 ohms.

Can I hook up these three 8 ohm cabs to this amp? 

Maybe two in parallel into one channel (4 ohm load) and the third cab into the second channel (8 ohm load) and jumper the two channels together?

Or do I just use two of the 8 ohm cabs in parallel for a 4 ohm load into one of the channels?


Thanks.

[edwin]

You should experiment and see which works out best for you. I would start with two of the cabinets in parallel in one channel and the other into the other channel, with the amp in parallel mono and adjust the gains accordingly.

Are all the cabinets the same?

[rv_bass]

Thay are all 112 cabs.  One is a Barefaced, and two are Accugroove. I could try the Barefaced in channel 1 by itself, and the two Accugrooves in parallel in channel 2, adjusting the two channel volumes accordingly and see how that sounds. 

I probably will only rarely need all three at one time, maybe for outdoors settings, but would like to know what combination would work with these tree cabs.

The Barefaced has a smoother and fuller bottom end than the Accugrooves.  The Accugrooves are cleaner/crisper, but I can dial in more bottom end with an SF-2 to get them closer to the Barefaced. 

[rv_bass]

What I’ll probably do is sell the two Accugrooves and get another Barefaced, just thought I’d see if I could make it work with what I have now first, and knowing if the ohm loads were compatible with my amp was the first step.

[StephenR]

Not difficult to find a power amp that will provide 2 ohm output and be stable but using matched speaker cabs is always the best way to go, much easier to EQ one driver type.

[rv_bass]

Thanks, Stephen.  I would rather not buy a new amp, and I do like the Barefaced cab, so I’ll probably sell the Accugrooves and get a matching BB2.  I’m really loving the lows from the BB2, and mids and highs are tight and smooth too.

[JimmyJ]

I think you should try what you said 4 posts ago - run the single Barefaced cabinet off of one channel at 8 ohms, and run the two Accugroove cabs off the other channel in parallel at 4 ohms, then link the inputs or send the same signal to each from your SF-2. (Can the SF-2 send two mono outs?  Or you could get crazy and run it all in stereo...)

Your power amp rating is rated at 725w into 8 ohms and 1000w into 4 ohms so you've got PLENTY of headroom.  The only thing you want to avoid is dropping the total impedance below 4 ohms because power amps don't like it when you get too close to "shorting" thier outputs.

Jimmy J

[hieronymous]

This is all I've got





(Sorry, couldn't resist - get it?)

[lbpesq]

ROTFLMAO!

Bill, tgo

[rv_bass]

Thanks for the comments, guys.  For now what I will do is use the Barefaced when I only need one cab, and the Accugrooves when I need two.  That should solve the dilemma. 

[rv_bass]

WALSTIB 

[pauldo]

WALSTIB 

I had to Google that.

Paul (call me Boomer)