I have a 4x12 rated at 240W.
The general rule of thumb with these Peaveys seems to be twice as much power handling in the cab as the amp is rated at (i.e., 120W amp into a 240W cab). I can't remember the reasoning behind this but most people seem to be very wary of the 120W cab for a 120W head idea.
Make sure you have enough power handling capability.
I'm not sure if two 120W 212s still only allows each cab to handle 120W, or if the load is divided between the speakers so that together they can handle 240W. Regardless, even if the latter were the case, the total would be determined by the lowest rated cab. For example 120W & 100W cabs in parallel would give you 200W if my hunch is correct, not 240W. If on the other hand you only get the capability of the lowest cab you would only have 100W before the smaller cab blows
If you mix speakers in a cab apparently the power handling is the rating of the lowest-rated speaker multiplied by the number of speakers. However I have seen speaker cabinet manufacturers make the mistake of rating a mixed cab by adding them together (e.g., rating a cab with two 60W speakers and two 75W speakers as 270W when it is actually 240W). This makes sense if you remember that there isn't a little man inside your cab sending more watts to one speaker than another. The load is always divided by the number of speakers so if you pump 270W into that cabinet which is really 240W two of the speakers will fail. Does that make sense?
Anyway maybe someone can clarify this. Worth being clear about it before damaging expensive stuff
