The head is a Mesa Maverick short head, and the outputs are 4, 4, and 8 Ohm. My cabinet is an Orange 2x12 with a pair of 8 Ohm Celestions wired in series for 16 Ohm. The Mesa docs say that you can run mismatched, but going too low will accelerate wear...it doesn't say anything about going going UP. To further confound things, I have a Mesa Maverick 4x10" combo. This amp is the long version, which has a slightly different chassis configuration. The labeling on its outputs are 4, 4, and 8/16 Ohm. I'm surprised one is designed for 16 Ohm while the other isn't. Just a labeling thing, or is there really a design difference between the two versions of the same amp? So am I ok, and what (if any) effect will there be on tone, etc.? Thanks so much.