That repressed (distant? thin?) may be a symptom of having some of the speakers out-of-phase. Since this seems to be most of a problem with CD in stereo I suspect that your left and right main speakers may be wired out-of-phase. Check the speaker connections and make sure The + and - (red and white or red and black) wires are connected to the correct terminals both at the receiver end and at the speaker end. Unless your speakers are incredibly hard to drive the Denon should at least be able to make them sound better than the Bose 301's.