Eric,
I'm using an XMOS/Wolfsen USB DAC clone/prototype from a Chinese vendor. It's quite good, as most of them are.
I'm also using Audience interconnect cables John provided and the 30/130w power supply. This reminds me of sitting in Eric Alexander's garage in 2007 listening to our Axis Grand prototype. Tweeters there were ribbons and a Hivi midrange, but there were so many of them firing together it was information overload. I killed that speaker because the bass sucked and they cost me too much to make and have shipped here.
Hard to believe you can get all of that in such a small package. These 3-inch drivers with huge magnet structure push more air than a typical mid-range in a full-sized speaker. With a low-bass sub, they're performing like much larger speakers - but almost perfectly linear in the mid-range and very revealing highs.
I don't have a golden ear, but the clarity is unmistakable and I can crank up louder than I'd want to at close range without loss of fidelity.
Seth