The wait is over! FXT90s were waiting for me in my mailbox when I got home from work yesterday. That's a mere 10 days after I hit the "Buy It Now" button on ebay... No small feat.
My disorganized impressions thus far:
-Build quality and design are exactly what I expected--sturdy construction, just enough weight to them to make them "feel" durable, and they look classy in an unassuming way as befits a pair of $120 phones. Microphonics aren't great when worn down, but a non-factor when worn over the ear. Isolation is strictly average.
-I've got driver flex on both sides, but I don't really see/hear what all the fuss is about. Makes for some squishy noises while inserting them, but is otherwise not at all present. I have a feeling this would go away entirely with different tips, as the stock medium tips do give a fairly vacuum-like "sticky" seal in my ears.
-As for the sound (after only 6-7 hours of burn-in), it's pretty much exactly what I expected: these are really up-front and in-your-face headphones. To put it in spacial terms, it kind of feels like sitting 3-4 feet away from a pair of stereo speakers with about 4 feet between them. The soundstage width is a bit limited because everything feels so close to my head, but not to the detriment of L/R separation. The dynamics/depth are really nice, and the instrument separation is spectacular. I've never really heard such obviously "coloured" headphones manage to achieve such surgical precision when it comes to instrument separation. It's a really cool effect--a very natural, musical sounding 3D effect. Actually, given this, I feel like a wider soundstage would push these over the edge into "fake surround sound" territory, so I can understand the decision to keep the width reeled in.
-Bass/Mids/Highs: In keeping with my expectations, a very pleasing amount of bass (not hearing the mid-bass hump yet myself). Bass is adequately thick, somewhat to the detriment of clarity... Again, it reminds me of a good home stereo woofer in that it provides a satisfying amount of impact and presence, even if it downplays the detail somewhat, especially compared to the mids + highs.
Speaking of which, the mids are really nice. Very crisp, fast, detailed--as advertised!
That said, THERE IS HARSHNESS. I hear it in the upper-mids/lower-highs--the nasal frequencies. Tom Verlaine's voice on 'Adventure' (by Television) is nasal to begin with, but these cans take an already difficult voice and make it practically unlistenable. I find they also bring out the less pleasing elements of upper-mid-centric clean guitar tones and snare drums. I'm really, really hoping this "honkiness" mellows out with burn-in, as it currently makes these headphones unnecessarily fatiguing, albeit mainly on tracks that prominently feature that frequency range.
Otherwise, the sparkle and detail in the highs is great. The treble is not inherently cold or harsh, but rather it's that one spike in the high mids/low highs that jumps out as the lone sore spot in the frequency range and in a sense casts an unfortunate 'coldness' on the overall character of the FXT90s. I definitely plan to let these burn in a bunch before making any rash decisions, and I may also order a set of M11 tips in an effort to improve isolation and tame those upper mids if they don't go away on their own.
Overall, these sound classy and I can undoubtedly hear their potential--enough so that I'm willing to be patient with them for a few weeks. They are otherwise exactly what I was looking for--a near perfect blend of detail/separation/3Dness and musicality. If/when the harshness goes away, I'll be perfectly happy to make these my go-to pair of cans for the next few years.
