mark iv slave out into 2xel34 classAB

[ibanez4life SZ!]

You want to be using the Slave out here.

The Slave and DI are not the same thing...the DI is more of a recording function, sending the signal out of the amp at a fairly low level for recording.

The slave out you can connect to your poweramp, and then run the Mark IV and the slaved poweramp into two jacks of a stereo cab.

Simply, and no extra boxes

 

[ibanez4life SZ!]

If you're courageous, you could wire the cab for stereo fairly easily.

Otherwise, I can't think of a different way to do it with your cabs without adding some sort of a switching unit.

 

[JOEY B.]

when you slave out of amp A, do you plug an instrument cable from slave out of amp A into input (preamp) of amp B or into effects return of amp B?

Effects return of amp B. And sneak up on the slave and master volumes, to be safe.