I borrowed the D33 over the weekend (it has to go back to the dealer tomorrow for another demo sadly) and it sounds very nice indeed. I'm using it via USB mainly (from a PC) and an ipod using the Wadia 170. The USB cable is some patch lead I had lying around and the Wadia is using the digital cable it came with. The D33 is then connected to a Musical Fidelity M1 HPA with Cardas golden reference and that in turn is driving Cardas cabled HD800s.
I don't know how much time the D33 has spent running in, so treat my comments below with a pinch of salt - my Musical Fidelity stuff changed in character completely over the first 150 hours.
Incredibly musical and beguiling, very easy to listen to, and no fatigue from the HD800s whatsoever. That makes a nice change :-)
It has a rounded sound, rich and deep, with detail that doesn't force itself on you but is there all the same.
It sounds good with everything I'm playing through it, classical, pop, rock, metal, trance, you name it.
It lacks airiness. The treble is all there and detailed, but it doesn't breathe in a way I know the HD800s can.
The bass is big and easy going, but it could be better defined. The word 'rounded' works both ways...
It looks like it costs £200 not £2000. It feels really solid and weighty when I pick it up, but on the rack it looks very average. The tactile sensation of the buttons isn't wonderful either.
The direct ipod input on this one doesn't work, either with a 4th gen ipod or a 1st gen ipad. It may be faulty, or the design may be hyper-sensitive - a sample of one makes it hard to tell.
When I switched to the Wadia to listen and subsequently ejected the CD whilst Foobar was still playing it the D33 had a bit of a wobbly with the music (from the Wadia) stuttering for a couple of seconds. I briefly wondered if I'd failed to switch inputs on the D33. I don't know if that's a Wadia issue (coincidence), or if the D33 got confused for a moment.
I put a pan on the stove yesterday and decided to listen to a couple of tracks whilst I waited for the water to boil. I've no idea how long I left it, but by the time I remembered the pan it had boiled dry and wasn't looking too good... I've never done that before, which says something! I really like the D33; its supremely easy to listen too, makes everything sound interesting, and works well with most of my music collection, whilst being more detailed than I sometimes realise. But its not perfect, the lack of airiness being my biggest issue (it's why I bought the HD800s even though they sounded way too bright in the demo), and at £2k I'm going to be hyper-critical. I'll try it again in a few weeks, hopefully for longer in case it opens up after prolonged use.