Not sure about that damping factor info. My 755 manual lists it at 850 up to 400Hz. This is actually higher than typical. Most of my other amps have been in the 150-300 range. Much over 200 is tough to achieve in practice due to cable resistance. So my guess is because the 200 is from the same heritage, the damping factor (Low Freq) is probably 800, not 80.

My question is why are there 2 RCA input jacks to a mono block amp? Should be just 1 unless they are using an RCA for the trigger jack instead of a miniature. Any clues out there? My only thought is one of them is for auto-on and the other is for no auto-on.