BlueR,
Theoretically, there is probably little if any practical sonic difference attributable between damping of 300 versus 1000. The consensus seems to be that most speaker wire electrical properties alone negate any differences once damping passes 50 or so. I moved from Carver amp <50 damping to Musical Fidelity at around 50 to current Bel Canto with damping 1000. The Bel Cantos seem to have the most controlled, dimensional and articulate sound top to bottom of any of these with the OHMs by a wide margin. There are many factors that might account for how a Class D switching amp performs versus conventional Class A or A/B. In a nutshell, the 500 w/ch Bel Canto ref1000m amps drive my large Walsh 5 effortlessly and without breaking a sweat at any volume I have attempted. They retain mostly the same sound quality at any volume, however as the volume goes up teh music becomes more full bodied, dynamic and lifelike, like blowing up a balloon. Never any sign of strain, clipping or noticeable distortion at any volume. Things just keep expanding and becoming more full bodied and lifelike as the volume goes up. Midrange is very clean and articulate. Vocals are lifelike and lyrics clearly understandable with most any decent or better quality recording.