Front end is DCS. I will get back to you on whether it was running on battery power or not. I asked Jeff yesterday and didn't get a straight answer, so I'll assume it was not. I was in the room today but focused more on listening.
The set up is very good. I think it tended towards the bright side, but overall a rather detailed and transparent sound. The Criterion is a couple steps above my Capri, but overall it has made me have a greater appreciation for what a great value the Capri is.
FWIW - many rooms at the show appeared to sound bright to me. The set up is difficult due to most rooms having a double tier with railings. The Rowland room was one of these so I have to give Jeff credit for getting as much out of the room as he did.