Before I sold my Denon DVD-5910CI (retails $3800), I did a little comparison one last time just for my own good. I compared the 5910CI with the Denon Blu-ray DVD-3800BDCI ($2000) and a lowly Sony DVD changer ($130). I listened to my favorite CDs (2Ch). As hard as I tried to hear a difference, especially between a $3800 player and a $130 player, I could NOT hear any difference whatsoever. But that's just me.
I suppose someone else might have been able to hear a difference.