I nabbed the AI-101DA in a previous drop. I've had it for a month and I'm still evaluating the unit, but so far so good. I'm running it through a pair of NHT SB1's and a Acoustic Research S108PS 8" subwoofer (AR is now defunct but this li'l sub keeps on going). I compared this set up to the Kanto YU3 powered speakers I also got from Massdrop. Here's my very unscientific evaluation.
My research revealed that the AI-101DA runs ALL input through a DAC prior to output. That is to say, incoming analog signals are sent through a A/D converter before sent through the D/A converter. Why? Heck if I know. However, I did notice a bit of background noise when increasing the volume w/o music, so it's not dead silent. When playing music though, the background noise is minimal, very minimal. This was with both speakers and headphones. Why? Again, heck if I know. Background noise on the YU3s was very low w/o music and the volume turned up.
The YU3 via aux input was... impressive. They had a nice soundstage, good vocals, good mids and highs and being ported, had a bit of impact in the upper bass. The Teac w/the SB1s produced more detail (as the SB1s employ a titanium dome tweeter as opposed to the fabric one on the YU3) and good overall sound and midrange BUT... seemed a little compressed at low volume. At higher volumes, the Teac blossoms and there's more detail and impactful mid bass. This may be due to the SB1s being not exactly easy to drive and that they're happier when fed more juice. But overall both systems sounded pretty good even when pushed. The YU3s seemed to perform in a manner that belies their size, and I was impressed with both systems when I challenged them with higher volumes. The YU3s seem to have a built-in limiter to prevent distortion. Smart. The Teac can be driven into distortion, but unless you wanna ruin your speakers or annoy the neighbors, why on Earth would you do that?
The BIG difference was when adding the sub. For music I used Average White Band's "Pick Up The Pieces (Nu Jazz Mix)" from their Latest and Greatest disc and Seals and Crofts "Summer Breeze (Phillip Steir Remix)" as both contain some low bass material. (I'm also an old school funk fan... DONT JUDGE ME.)
Dialing the sub in to work with the YU3s sub output was labor intensive and I had to turn the volume on the sub up higher than I expected before they blended. Once I did, the sound was fuller... but lacking the impact expected. Then I switched to the Teac/SB1 combo and.... NEARLY BLEW THE SUBWOOFER DRIVER OUT. I had forgotten to turn the sub volume DOWN! The sub output from the Teac was fur realz! I mean, it kicked! Once I got the crossover and volume dialed in... it was MOST impressive. With the Kantos I had to turn the sub volume to nearly three-quarters before it seemed to come to life. With the Teac I can keep the sub volume at one quarter and dial in the crossover... and you hardly notice that the sub is there EXECPT when the music calls for it. But when it does... whoa.
The only conclusion I could draw from this is that the signal output and crossover in the Kantos sub section is a little weak and not well implemented, while the same in the Teac is high and top notch.
Don't get me wrong, I really like my Kantos and they would work great alone or with a sub in a bedroom, office, dorm room, desktop or even as a step up from inexpensive soundbars. But the Teac with the right quality speakers AND a sub could work as a 2.1 living room system and would shame all but the most expensive soundbar/sub in a box systems you might find at (heaven forbid) Best Buy. My only regret about this purchase? I was late to join the drop, missed out on getting the silver version and had to settle for the black. ¯\_(ツ)_/¯
And that's my 2¢. Next, I have to compare the Teac to my NAD C316 BEE integrated with the NHTs. Fun times.