I have been using two DAC1 (ver1) since many years now - professionally, so I know them and their shortcomings intimately.
Since a month I have been testing, using and ended up buying a DAC2.
I can confirm that the difference is there, in all aspects and it is a very big upgrade compared to the DAC1.
In comparisong the DAC1 is veiled, rough and at the same time closed in. Relatively speaking that is, I still find it an amazing DAC at the price.
We tested the new DAC2 against Weiss DAC202, Gracedesign m903, Bricasti M1 and the new Bryston BDA-2.
The DAC2 was very clearly superior to the Weiss and the Gracedesign (although I am a big fan of Grace, all our mic preamps our by their design).
The Bricasti M1 (costing 4x more) was hard to compare to. On its proposed filter setting (Stereophile), it was tossed out as inferior straight away. Digging into the filter settings brought the maximal performace to the surface, and it was a slower minimal phase filter that brought it on the same level as the DAC2. We never understood why they choose to included all those filter settings... (and I am a big fan of Bricasti, we have and use their M7 reverb processer, it is simply amazing)
The Bryston BDA-2 was very intruiging, as it was very very close to the DAC2. But no volume control, no headphone preamp, so on practical consideration it was tossed out.
The DAC2 managed to beat all of them, including the M1 on the preferred filter setting by the sheer listenability, it is frighteningly clean, but at the very same time utterly musical. It has been the first time since a decade I find myself listening in the studio to music I am not working on - just for pleasure.
I think that says it all. You want to listen to it. That is a hard feature to beat in a DAC.