three cabinet stack?

tdogg · #1 03-19-2010, 05:30 PM

i recently got (built) a new BFM J112. i love it and i want more. i was thinking of building 2 more for a total of a 3 cabinet stack. 8 ohms each (three 8ohm cabs in a row = 2.6 ohms right? how would i wire this?). any one else running three cabs? pics and details would be awesome!
BTW my power amp is a mackie 1400 so impedance should not be an issue.

kesslari · #2 03-19-2010, 06:16 PM

Sort of.
I'm running a BFM Omni10 (2 10's 4 ohms) and an Omni10.5 (110, 8 ohms). 2.67 ohms total, more or less. I run a Genz Benz NeoPak (2 ohm capable) and it rocks.

I love it. I use the 310 stack for big gigs, the 210 for most gigs, and have a 110 for coffeehouse gigs.

tdogg · #3 03-19-2010, 06:28 PM

very nice. with your setup ( a 4ohm and an 8ohm) does this mean that the 2x10 gets twice the power? then all 3 speakers get equal wattage right?

Bob C · #4 03-19-2010, 06:37 PM

The only thing cooler than a three cabinet stack would be a four cabinet stack!

I'm not sure what you mean by "How would I wire this?"

If the cabs have two parallel speaker jacks, just daisy chain them together. You can do this with all three cabs, or run one separately (sp?) into another one of your amp's speaker outs (I'm assuming the Mackie has two spkr outs on each channel). Three cabs in parallel in one side of the amp will give you the same 2.66 ohms any way you plug them in.

IF you choose to use BOTH channels of your power amp, your only option will be to plug two cabs into one side, and one cab into the other side. Then adjust the volume levels with the power amp's controls. Nothing wrong with that.

Gintaras · #5 03-19-2010, 06:40 PM

get a head like a Neopak that will go down to 2 ohms. Will have no problem with running (3) 8 ohm cabs. Also many of the Carvin heads will go 2 ohms. I am using a Neopak and have numerous combination of cabs with it.

I presently have a scenario like the post before. A 2x10 4 ohm and a 1x10 8 ohm but these are Schroeders. I have not had a chance to play this configuration out but they seem to be fairly balanced.

Bob C · #6 03-19-2010, 06:50 PM

I thought the Mackie went down to 2 ohms per side. If it doesn't, you can still run two cabs on one side and one cab on the other. The only thing you should NOT do is run it bridged with three cabs (2.6 ohms).

Gintaras · #7 03-19-2010, 06:53 PM

Quote:

Originally Posted by Bob C

I thought the Mackie went down to 2 ohms per side. If it doesn't, you can still run two cabs on one side and one cab on the other. The only thing you should NOT do is run it bridged with three cabs (2.6 ohms).

sorry that I missed your last line that you have a power amp. Sounds like it should be easy to control it with a power amp with 2 sides. Even if it is 4 ohms, you can run 2 cabs on one side and the 3rd on the other.

babebambi · #8 03-19-2010, 07:00 PM

1, 2, 3 ...

tdogg · #9 03-19-2010, 07:02 PM

the mackie does go to 2 ohms safely in "non-bridged" mode. it has a "stereo/channels summed/bridge" switch on the back. i need to find out if that means i can use the "summed" switch to run full power (non bridged) from one output. i hope thats what it means

JGR · #10 03-19-2010, 07:03 PM

I had three S15-D's for a while (have two now). Worked great with my SWR Power 750's which do 850W into 2.7 ohms. Also worked with the 800RB doing 100 watts into the top and 300 watts split into the bottom two.

tdogg · #11 03-19-2010, 07:07 PM

Quote:

Originally Posted by babebambi

1, 2, 3 ...

i want your bass....

Bob C · #12 03-19-2010, 07:21 PM

tdogg,

Yes, check with Mackie tech support. I am almost positive that "channels summed" means the same thing as "parallel mono" or "dual mono".

If so, that means one source going to two channels (A and B), but not bridged.

The difference between that and "stereo" (when talking power amps) is that stereo technically is running TWO sources into two channels.

Anyway, I'm 99% sure that as long as you're not in bridged mode, you'll be fine. But check your owner's manual or give Mackie a call.