I am an avid aguilar fan, I understand alot about the amps and love using them.. A couple of things I've never been able to figure out.... Names. I understand what the DB stands for but what about the numbers? The DB750 is self explanantory. What about the 359 (It's a 200 watt amp), the 728, the 680 and 659 and the 924? Does anybody know??