Hi. I received one of the Zen Air Dac units this morning on loan from iFi. They asked if I would have a listen to the unit as I already own the Zen Dac V2 and give review on how it sounds. I am not the most technically minded person all I can give is my own impression of how I find the unit. I have been able to do a side by side comparison as I have both units hooked up to my iMac just switching between inputs. I am not going to say a lot about the Zen Dac V2 as I have already commented on this unit which in all honesty I find it to be an excellent unit which I use very often and I am very familiar with. Lets go on to the Zen Air Dac, this is a less expensive unit than the Zen Dac so cannot be directly judged. There is a price difference of £60. The Air unit only has a single ended 6.3mm output whereas the Zen Dac boasts a balanced 4.4 Pentaconn output which is of course handy if you own a pair of Balanced headphones which is not the case with everyone . The Air unit has Xbass+ for bass boost which differs from the Zen Dac unit which has Truebass. I have both units with the relevant bass switches on for comparison purposes. Cosmetic appearances differ in that the Air unit comes in a Grey metal case which I find attractive but is a bit more basic than the Zen Dac unit but if I had more than one of these units from the new Air range I think that they would compliment each other. Sound conclusion: The Zen Air Dac is by no means a slouch it does in fact sound very good and if my budget had have been lower I could happily live with this unit. The unit was tested using an iMac connected via USB cable supplied with the unit which carries both sound and power using Monolith M565C headphones listening to various Genres of music. All in all another fine product from iFi. I have no affiliation to the company. Thanks for taking the time to read my comments.