it seems like "edbass" knows pretty much everything about hooking up amps properly. so if you or anyone else could help, thatd be great!!
thanks a ton- justin
Well... thanks for the vote of confidence Justin, but the truth is that my impedance "knowledge" is kind of a joke on this forum. Sometimes I make some pretty grievous errors regarding parallel and series, etc. I
do know how it works, but for some reason I get ohms dyslexia, so I'm not your best bet for hookup info.
I generally use a multimeter before I turn on power, just to be sure.
As far as your question, I’m not a Marshall expert, but I think you have two outputs wired in parallel with a selector switch for 8 or 16 ohm loads. If you plug in two cabs they both need to be 16 ohm. Your 1960A is a stereo or mono cab, but your JCM is a mono amplifier. Your 1960A can run either 4 or 16 ohm mono; I would run it at 16 ohms by itself with the selector switch on the amp at 16.
If your Sunn cab happens to be 4 ohm, you can run it as a full stack, but you would need to rewire it to 16 ohms. That would entail putting all four 4 ohm 12’s in series instead of series parallel that it probably wired as. IF it has 4 ohm speakers in it. If it has 8 ohm speakers, you’re probably out of luck as far as a full stack goes.
If you can get the Sunn to 16 ohms, plug it into one output on your JCM, and the 1960A into the other jack and put the selector switch to 8 ohms.
Clear as mud?
Hopefully someone else can post with other suggestions, but this is about as far as my Marshall knowledge goes.