I decided to edit this post so as to save anyone who might spend any real effort replying some time. By all means I'm happy for any discussion to keep going, but I did discover an old Adcom preamp in my attic with a phono input and it sounds great using some XLR-RCA adaptor cables and a Nobsound switch box that lets me still control digital sources with my RME DAC and analog ones with the Adcom. Quite a sturdy pre-amp and personally I love the sound both with the tone controls bypassed and active. Nelson Pass designed the first generation 555, FWIW, and he commented elsewhere that Adcom made a few changes w/ the Mk II. If I'd known I had it up there, I would have sent to Amir to test a year ago, damnit, but now it's stuck in my system...really is quite a nice little preamp especially for its age.