Pros: Detail, Bass body, Treble, PRaT, Soundstage, Dynamic
Cons: Needs right setup, Somewhat recessed mids, Fatigue
The DT990 is my first HiFi headphone after the AKG K181DJ and also my ticket into the world of Head-Fi. First off, I have to say that my impressions are pretty consistent with what seems to be the mean impression out here on the web; I tried out al sorts of headphones that were comparable in price before deciding on the DT990. And I know now what it was that made me do it: the amount of detail and air between the different instruments. I tried the higher Sennheisers (HD6X0's, 5X8's) before I tried the Beyers and thought they were nice, smooth, definitely more refined and clear than my K181's. But when I put on the DT990 for the first time I was vortexed into another plane; I heard things in the music that I never heard before, even on my HiFi setup and even in songs that I (thought I) knew back to front. I was looking for a different sensation when listening to my music and there and then I found it. There was just so much air between the instruments, such darkness in the background and so much detail! These cans simply break the music down and make it possible to analyze every single part of it.
In the recent years, though, it became clear to me that the things I love most about music are smooth, dynamic bass- and midsections. However, while the bass is very dynamic in it's stock form, it's not always smooth, Jamiroquai is one of my all time fav bands and a great deal of their repertoire fell prey to the DT990's overpowering and boomy bass. The mids, which indeed are a bit recessed compared to the rest, weren't as smooth either. When I became aware of this flaw I decided to see whether I could find a pair of phones I'd like better in this regard. But the Senn's were much to slow and 'veiled' they felt too congested overall; the Grado's practically threw me on stage (talk a bout a shortage in subtlety), didn't wow me in any way and the AKG's I found lacking too much in Bass and mid's altogether. I decided to take a different approach to the whole DT990 issue and started looking at the dac's and amplifiers available nearby. After many hours auditioning I came up with this setup: MacBook > HRT Microstreamer > QED > Musical Fidelity X-Can V8P > Beyerdynamic DT990 250Ω. First the V8P it smoothens out the mid and high frequencies while defining the bass a bit better and creating a bit of warmer ambiance. Soundstage is deeper and a bit wider as well. The HRT completely tames the bass and high treble, which decreases fatigue to a minimum, and actually boosts a good chunk of the mid's while defining everything just a bit tighter. Now this is NOT to say that the bass and high's are muted or something like that, they are just refined by the Microstreamer. Neither does it detract any of the ambiance created by the V8P.
Noticed how all the "cons" i wrote down are practically nullified in my review? Out of the box these sound pretty good, albeit a bit fatiguing... get the right setup though and watch them truly live up to their potential!