#1
I have a 50watt JCM900 2x12 combo and a JCM900 Slant 4x12. I want to use all 6 speakers (3/4 stack I guess!)

The cab is 16 ohms (obvi.) and the speakers in the 2x12 are G12T-75's (8 ohms each). I'm no good with this impedance business, is it ok to do this?
#2
someone else will know better than I, but i think you can as long as the amp output impedance is set to 8 ohms?
Austin Les Paul rip-off that sounds really nice
Gibson V
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#3
You would need the cab to have the same ohm rating as the two speakers in your amp, and you would need your amp to have an extension speaker out so that it will run it's speakers and your cab in parallel. And you'd have to be able to switch it's impedance to half of what it currently is (probably from 16 ohms to 8 as mentioned above).

Keep in mind that when doing this, the two speakers in your amp would carry half the load, and the four speakers in the cab would handle the other half. It wouldn't be shared equally across all the speakers.
You Don't Need a halfstack.

You Don't Need 100W.

Quote by jj1565
i love you slats.