The *BEST* power amp

Hi Everybody!! Wondering what yall think is the best power amplifier (no preamp) in the categories of:

*THE ABSOLUTE BEST*:

best for under 1200:

best for under 900:

best for under 600:

best value:

By best, I mean quality of sound amplification. No tone coloring or crap like that, that should be handled by a preamp. Exactly what goes in comes out, except a whole lot louder. So what is THE BEST

note: You, my ears, and the friendly folks at guitar center are deciding my future investment in amplification. Whatever I wind up with will be dual use for both bass and keyboards. I've created three threads, one for power, one for pre, and one for cabs. It's just easier this way.