Agree with ma90 and others who say just that
- Initially believed that the missing base compared to its other handsets but it really probably is because these drives with frequent "boost" between 40 ~ 150Hz and those "clean out". The combination of a standard volt weak headphone output (with too high impedance) as one experiences it might just as (and are partly right without proper reinforcement).
- They are neutral and accurate, just as you want them (if you are on the fidelity in the truest sense), there are minor problems that can be minimized with good EQ
- Comfort is super; soft, clear with just enough pressure on my head.
- Build Quality!
However, few though:
- Well large, protruding cups're not so good ears pinched both in the xy stage but also in depth, but they are so big that the bottom half lightly rests against my jaw "attachment" and it is a bit tedious after a fairly short time. However, one can easily have their center point adjusted upward slightly but possibly becomes soundstage and tonal balance affected. However, after a few months I got used and cf. my HD650 (which is well hard, hot press), they are as comfortable overall
- A neutral, quiet, distortion free, high power amplifier (e.g., the superior Objective 2, see http://nwavguy.blogspot.com) of low output impedance (check e.g. http://www.innerfidelity.com/content/comparison-beyerdynamic-dt-880-32-ohm-dt-880-250-ohm-and-dt-880-600-ohm-headphones) is quite important for them (like most> 50Ohm lurking). However, I think they work ok with eg Fiio E6 or if it's quiet / you do not want to rock out without external amplifier (running Nexus 7 and iPhone 4S with ok results ). 250Ohm is "perfect middle ground" against 32 or 600 IMHO.
- Treble around 7-9kHz seems to be a resonance or similar so I need to EQ down a dip there to not cymbals, s-like sounds to get it there "shimmering effect" as many sometimes think is "hi end" but is not realistic but sometimes (depending on the material) a little tiring. There are around 6-8kHz as your ear canal has its resonant frequency so this is a bit difficult to adjust without sine waves, the right software and a lot of time;) (see incidentally http://www.head-fi.org/t/413900/ how-to-equalize-your-headphones-a-tutorial)
- 1-3dB extra heat register (~ 80-250Hz) can do it all ... ehh .. warmer and possibly closer to the original but be careful not vote becomes cloudy / "boomy"
- Steel arches could be polished a little finer, now they have some sharp edges.
Compare it straight off the HD650 is almost exactly the inverse of one another regarding the tonal balance so it's fun to change and try to have different EQ settings and get them to Like! Another. HD650 makes everything sound as "beautiful" and forgiving but a little weak attack. DT880 is a scalpel in comparison but may lose some of the "fun factor" and one can tire of good music that is poorly recorded / mastered / komprimerad..bra with alternative words.