Well, I finally got my levinson 331 amplifier back yesterday (thank you Harmon International). I immediately set it up and voila, back to musical heaven. The amplifier made a huge huge difference in sound. I retract what I said in my previous post. I believe that the model 10 is better in cd playback than the model nine signature, but it is not a huge leap in sound quality. Where I notice it is in the bass, which seems tighter and slightly deeper than before with the signature nine version. The midrange and high end are once again back up to their stellar levels, and if anything slightly cleaner (without being edgy) in the top end that they were before. I can again hear the nuances I was missing before. My sincere apologies to Muse - I was wrong. I have not compared video quality as I lack a truly decent home theatre set up, nor have I compared dvd audio quality as I only have two dvd audio disks to play. But for cd playback the muse 10 is better than the nine signature. I do want to emphasize that it is not a huge difference, but it is an apparent one.