When you said that you were disappointed about the sound of music, I was going to suggest turning off your Dolby Pro Logic, and just play in Stereo.
I do not know if Harmon Kardon has a similar format, but Denon recievers have an excellent 5/6/7 channel stereo format that is excellent. It makes a surround system work like the 4 speaker system in a car by duplicating the channels in the rear and allowing only a small amount of bleed to the center. Otherwise just play music the way it was meant to be heard, in stereo.
