Just been reading up on the old Genz Benz shuttlemax series, and specifically the max amps, becuase they have 2 independant preamps, which is very handy.
Here's the crux of the biscuit - the 12.2 max ( and the earlier 12 max ) not only have 2 independant preamps but 2 independant power amps. Now,... if you only use 1 cab , you get reduced wattage. 1 x 8 ohm cab = 375 watts. 1 x 4 ohm cab = 600 watts. These watts double if using 2 cabs of equal ohmage
Now then - the 9.2 max ( there is no earlier 9 max ) still has 2 independant preamps, but not 2 power amps. So running 1 x 8 ohm cab = 500 watts and 1 x 4 ohm cab = 900 watts.
I dont see the point of the 12 and 12.2 max amps having their power amps independant. ?
12.2 max specs
http://www.genzbenz.com/?fa=detail&mid=2825&sid=715&cid=95
9.2 max specs
http://www.genzbenz.com/?fa=detail&mid=2664&sid=715&cid=95