Yea, Amp pairing with the LCD-3 is tough. My LCD-3s sat on the sideline for over a year until I came across the 600i. The 600i sparked my interest in the lcd-3 again, I could tell something special was going on and when I swapped the internal DAC with some other DACs...a couple sounded worse and a couple sounded better...fell in love with the Mojo combo and have a Chord Cutest on order to, hopefully, take it even further.
I have never heard DACs sound so different from one another than with the 600i. A testimony of its neutral/transparent character.