So I lied, cruised into work yesterday and listened for 4 hours.
Initial impression - it's not quite what I was expecting, it doesn't sound like what I have in my head as 'the NOS' sound. It's very fast, extended (@ both ends), detailed, energetic, etc, tipped a bit toward bright. Has very good slam. Sound signature-wise it probably has more in common with the Saber DACs I recently owned (Anedio/Minimax) than my Ack Dack, yet with better timber and a lack of digital sheen. Unfortunately I no longer have those for a direct comparison, but it is certainly a significant deviation from my TDA1545 Ack. This is more along the lines of how I'd expect one of Audio-GD's r2r reference series DACS to sound. It's very athletic. Honestly I was a bit fatigued after a 4 hour session, which is one of the reasons I believe I'm attracted to 'the NOS' sound, I can just sit back and relax for hours on end w/ my Ack!. But the Ack! definitely has deficiencies - it doesn't 'rock', it's rolled off a bit on the top and bottom, it lacks resolution, and bass is a bit soft. But this Metrum... threw on Appetite for Destruction, and wow, it really sounded better than I thought it could sound on my Edition 8s, the guitars sound just like they should, and it was a pleasantly brutal experience , at least thru my maxxed WA6Se w/ Sophia 274b. So far just using Redbook, now have an Audiophilleo 2 on the way as well as an EML 274b for the Woo.
That's about all I should say for now; the designer instructs it needs burning in for a couple weeks to settle the treble. Plus I'd like to hear what it does with higher res audio.
Edited by bobeau - 9/25/11 at 3:19pm