Hi Jprice, I have about 150 hours (low volumes) on my C500 and although I feel it is already an across-the-board step up from my former integrated amp (Plinius 9200), the bass of the C500 doesn't seem to be as textured and nuanced as the Plinius. In your recollection did the bass of the C500 improved considerably at the 200 to 300 hour mark? Speakers are Dynaudio C1.