Standard -
(Current Production)
One Power Supply, 60,000 uF - 30,000 per channel, Red Board
"Plus"
One Power Supply, 120,000 uF - 60,000 per channel, still red board
"Extreme"
Two Power Supplies, 240,000 uF - 120,000 per channel, red board
"Extreme II" (As I shall call it)
Generally the same configuration, a better circuit board - twice as thick with far better traces. Which leads to better signal transfer but is harder to work with...
Then of course there is dual mono and mono blocks. Dual mono is basically two "standard" versions in one case. Two power supplies, two sets of 60,000 uF (120 total), two power cords, etc etc
Mono blocks of course are two seperate cases, same thing listed above, just dedicated to one channel.
Older amps will have the same configurations, but the older green board.
A little scatter brained, but insomnia sucks