Here's my situation and hoping someone here can offer me some guidance. I've had a silverface Twin Reverb for about as long as I can remember. Is an amazing amp, but was never happy with any distortion pedal I stuck on it (even tried pedals with tubes). I recently picked up a Mesa/Boogie Triple Rectifier half stack. However, when I go jam at friends' houses, I don't always want to lug around the 4x12 cab, so I was thinking I could use the Twin as sort of a 2x12 cab. Looking at the back of the Twin, I see the input jack for the main speaker, with an external speaker jack next to it. Under each of them it says 4 ohms. If I unplug that (and obviously NOT turn on the Twin) and plug it into the Triple Rec, do I plug it into the 4 ohm jack? My first reaction was to plug it into an 8 ohm jack. I'm new to the whole impedance thing, as this is my first non-combo amp. I don't want to fry any gear!

I was also considering getting a Tonebone Headbone VT and use both heads. Anyone have experience with one of those?
Did you not get a manual with your Mesa that lists all the safe impedance matches and mismatches?
1992 Gibson Explorer (Seymour Duncan '59 neck, Custom Custom bridge)
Jackson King V Professional Std. (Seymour Duncan Invaders)
Mesa/Boogie Nomad 55
Mesa/Boogie 412 Recto. O/S Cabinet
Boss ME-50
MXR 10-Band EQ
Those jacks are the outputs, not inputs. If you follow the cable you should see that the speaker cable is wired right to the speakers, then plugged into the 4 ohm main speaker jack. Plugging your mesa into any of those 1/4 inputs will blow up at least one of the amps.

If you wanted to use the Twin's speakers, you'd probably need to rewire that cable, since it won't be long enough to reach a head on top of the cab. You'd plug that cable into a 4 ohm ouptput on the Recto.
Yes, that would be the better option. A twin still weighs 90+ pounds, and if you sold it and the 4x12, or even just one of them, you could get a great 2x12 that sounds just as good as a 4x12.
Yes, I want to hook the Mesa to the speakers, which is what the title says. Was just curious the proper impedance. I understand I'd need a different cable. I just want to confirm the 8 vs 4 ohm. I've looked at te manual, but as I stated, I'm not familiar with it all. I'll look at how the speakers are wired (i.e. In parallel) when I get home.

Selling the 4x12 is not an option. This solution is just for small jam sessions. Weight isn't the issue, space is. And I refuse to sell the Twin, I want it's clean tone.

Thanks all for the help so far.
Have 2 8 ohm speakers wired in parallel. According to the Mesa manual that's a 4 ohm load. So I should plug the speaker into the 4 ohm output? Just like Roc8995 said.

Thank you for the help.
Last edited by dmoczulski at Jun 22, 2011,