This is a rare chance to own a master piece from Master Guo, a long time audiophile and tube audio expert in Seattle, WA. The Shanling CD3000 is built like a tank with decent sound quality originally as most of us already know, and Master Guo further lifted it to a new level with extensive mods to beat most 5k-10k cdp imho. Most of us (included me) are not tech guys stick with specs and jargons, but if you want to know what had been done to this unit, I can try to give you some info here and there to assist your purchase. I have owned a dozen CDPs in the past 10 years as an audiophile, including the big players from Burmester, Meridian, dcs, etc.. I know you won't be disappointed with this wonderful machine at this terrific price. Come grab it quick!