Just received a pair of UE900s directly from UE. I have been less active on the Head-Fi boards in recent history because I've gotten more into speaker systems (especially tubes and vinyl), but I found myself in need of a better set of IEMs for travel and live monitoring. I hope you'll indulge me in a few thoughts on these new phones as they compare to my much used and abused Super.fi 5 Pros (whose performance and durability prompted me to stick with UE).
I've only been listening for a couple of days, but here's some initial impressions:
Very nice. Good looking box art, great box-within-a-box unpacking experience. Tons of tips types and sizes to tune the 'phones to my head. Two cords (one with mic and vol control). Nice hard travel case and a pouch. In terms of accessories, especially the cable quality, these blow away the Super.fi's as well as most other consumer electronics I've purchased in recent history. Apple-level experience.
Still trying tips, but as good as any other IEMs I've used. Had a couple of flights to listen to them on and they did a very good job of blocking the engine drone. Can't hear myself typing this right now.
Treble is very sweet without the graininess I sometimes get with the older UEs. Kick drums have a lot of complexity to the harmonics and cymbals are very natural. Good 'air' and ambience where it's in the recording.
Timbre in the mids is spot on. Strings sound natural, as well as woodwinds (two of the harder things to get right, in my opinion). Sax is especially very satisfying.
Bass digs deeper than the Super-Fi's. I miss the impact of a good 12 or 15 inch driver in a properly sorted speaker rig, but that doesn't fit in my carry-on. Still playing with tips to tune things to my liking, but it's so near ideal now that this is really an exercise in geekery.
Some spooky details here and there with live recordings (voices in the audience, room sounds, etc).
Balance is very, very good. Always felt the mids were a bit scooped with the Super.fi's. Even with some hardcore bluegrass, things are not getting congested.
I definitely need to step up my codec game. Mp3's sound pretty terrible up against loseless files.
I see some noise being made on the board about older revisions and repackaging, but more suspicion than substantiated fact. I've had the Super.fi's for probably close to a decade and never experienced any issues (did replace the cord a couple times, mostly due to abuse I've inflicted). I don't have any reason to doubt the UE900s durability at this point. If they're up to the standard I've experienced from UE (as well as many Logitech products), I think they'll last a long time.
I will be using these as monitors in performance settings, too. I do not plan to take it especially easy on them and will report back with issues.
I used to be very into headphones (still own some Grado 325s, Senn's, and the Super.Fi's, along with amps I've built over the years). I'm more into speaker systems now that I'm a home owner and without children. That said, I travel a lot and I work in the music industry so I've heard a lot of audio systems (earbuds to multi-thousand watt PAs). These are the best IEMs I've used and do some things better than my big tube amps and speakers can. Pretty ding dang good when portability is a factor, I think.
$400 is a lot for a pair of headphones, but an absolute value when you compare them to what it would cost to get the same level of balance and detail retrieval from speakers (live monitoring or home playback). I'm very impressed with the UE900s.
Sources: iPod Classic, MacBook, Profire 2626, Android phone (cringe)