I've have a review set of the iO-6 headphones, courtesy of Dali. I've not spent enough time with it to perform an in-depth review however have a few initial straight out of the box thoughts.
In terms of aesthetics, construction and ergonomics, I like it's presentation with it's carry case....rather chic with it's semi-hardshell case in denim-like material. The inside is felt-like which is soft on the headphone itself, and the zippers are far away enough to ensure it doesn't scratch the headphones. There's only one internal pouch to hold the charging and analogue cables.
As for the headphone itself, it's more delicate and smooth expressing a more sophisticated classy headphone (note I come from a primarily V-Moda portable headphone which has gone for a more rugged style). The synthetic leather of the earpads and headphone band also oozes finesse. The cups swivel and the earpads rock smoothly in perpendicular axes to each other which makes it easily adjustable. As for the arms that hold the cups, the slide is a little more stiff to adjust but once adjusted, it wouldn't slip accidentally. As the cups swivel, it hangs comfortably around the neck without any discomfort.
Around the head though, comfort is probably my biggest issue ergonomically. It clamps around my cranium rather hard so I can't listen to it long despite the flexibility of the earcups and earpads. I hope that over time though with gentle flexing of the headphone band, that it'll improve over time. The cups are circumaural and whilst I've read that some other reviewers state it's not deep enough, I don't have an issue with the depth for my ears. It is actually deeper than the V-Moda M-100 Master and Crossfade Wireless Codex (and these are the V-Modas with the deeper cups). I should be more specific that with the iO-6 cups, that the dust protector mesh to the top of the earpads are about the same as the V-Moda's however, the iO-6 dust protector mesh still sits a few more millimetres above the driver, whereas the V-Moda dust protector mesh rests right on top of the driver.
All the controls are on the right cup with physical clickable buttons rather than the Sony 1000XM series touch capacitive approach. Call me old school but I like the physical buttons more (and I used to own the Sony 1000XM2 before selling it off MDR-1000X before giving them to my nephew). The iO-6 button clicks are feel definitive like how buttons should be; folks would know in my V-Moda reviews (as much as I like V-Moda), their buttons are one of their weakest points feeling cheap/flimsy.
Whilst these days a lot of wireless headphones recommend having accompanying iOS/Android apps for greater control, the iO-6 has gone for just a more traditional straight wireless approach.
Sonically, my first thoughts were "these are like closed HD800s" (but no, not like the HD820s). The presentation is light and airy and sets the listener far from the stage. Attending many Tokyo International Audio Shows in the past few years, I'm familiar with Dali speakers and get the impression their headphone tuning comes from their experience with their speakers. The sound signature lends well to the classical genre where finesse in presentation is needed for the listener to subtle details complex orchestral piece. At least in my opinion, this is akin to the HD800 (and to a certain extent to the HD800S which I used to own too). Where I do wish more out of the iO-6 however is more bass slam, so listening to rock vocals (e.g. Billy Joel), or Dance, EDM, it's not as engaging. However with certain genre, it's exuberates a classy presentation for a wireless headphone.
