Running 3 cabinets off a Mesa combo amp?

[toejam]

My Mesa F-30 combo has an 8-ohm 12" Celestion Vintage 30 that's run into, of course, the 8-ohm combo speaker output. There's also two 4-ohm outputs on the amp for extension cabinets. Whenever I run my 8-ohm Crate 4x12 extension cab into it, both the Crate and the combo's speaker get plugged into the 4-ohm outputs. Could I also run a third cab through the 8-ohm output without any problem or would I need to get one of those little ohm series boxes?

[markD]

Re: Running 3 cabinets off a Mesa combo amp?

no. i don't know about an ohm box.

[Dreamland_Rebel]

Re: Running 3 cabinets off a Mesa combo amp?

yeah i don't reccommend it.

mesa does say that mismatching impedence doesn't "hurt" the amp but will wear on your pwr tubes quicker... but what your talking about just sounds like too much overload to me.

you'd be taking them down to 1 or 2 ohms and that can't be good for it.

[Fragle]

Re: Running 3 cabinets off a Mesa combo amp?

mmh....i'm REALLY NOT SURE (!!), but i think if you run two 8ohm cabs through the 4ohm jacks you're fine (definitely), and i THINK you could also run another 16ohm cab through the 8hom jack.

i kinda hate the spkr out jacks on those mesas anyway. you can't even run a fullstack (2 16ohm cabs) without having to deal with a mismatch - or an ohm box

greets
fragle

[Deneb]

Re: Running 3 cabinets off a Mesa combo amp?

I can run a full stack on mine without a mismatch. Mine has 2 8 ohm, 2 4 ohm, and 1 16 (IIRC) and Marshall cabs are 4/16 ohms.

The speaker outs are in parellel, so you have to figure your impedences in parallel. If the impedences in parallel are the same as the outputs, you will be okay, but these amps weren't designed to use 3 cabs, so I wouldn't run three cabs from it.

[toejam]

Re: Running 3 cabinets off a Mesa combo amp?

Thanks, guys! I thought I remembered something in my Mesa manual about being able to run three cabs in a couple different configurations, but I can't find the freakin' thing at the moment. I might as well stay safe and just do the way I'm doing now with running out of the two 4-ohm jacks. I'm also soon getting a pair of vertical Jackson 2x12 cabs that I believe are 8 ohms, so that should work fine and I'll just have to disconnect the combo's speaker then.

[Fragle]

Re: Running 3 cabinets off a Mesa combo amp?

yeah deneb, i think esp. newer mesas have those speaker jacks. the older ones however only have 1 8ohm out and 2 4ohm outs (wired parallel)

[Dreamland_Rebel]

Re: Running 3 cabinets off a Mesa combo amp?

mine only had 1 8 and 1 4. but its old.

go to the mesa boogie website and find there online manuels. i know that the rectifier manuel does have the speaker combination charts in it. as well as speaker wiring diagrams. i've found it very usefull for many things and i don't even own one. hehheh.