I've spent a lot of time with these over the last few days.. and remain very very impressed. They've clearly become one of my favorite universals.
While the shape of the phone might not look like it's possible, I love wearing them over-the-ear. It's very comfortable & in my case, I found the sound improves immensely (vs. wearing them "down"). I've never had much success wearing phones "down" due the shape of my (outer) ear. I just couldn't get a deep enough seal since most IEMs' cable/strain relief would bump up against the area at the bottom of my tragus.
While the FXT90 doesn't need a deep seat or seal, I still felt I wasn't hearing them accurately. The upper mids/lower treble were unnaturally harsh & fatiguing when the phones were worn "down." I got a seal but it didn't feel like it was deep enough.. the soundstage suffered too.. it felt like sound was leaking somewhere. Wearing them over the ear afforded a deeper (but by no means ultra-deep) seat and I was able to hear what these phones were truly capable of.
The bass already had excellent punch and definition.. but worn over-the-ear, they gained much more body, depth and texturing. I can't praise the bass response enough so it must be said again, the quality of bass these turn out is simply phenomenal. Deep, tight.. and luscious at the same time. I've noticed there is a very slight mid bass hump (or perhaps a slightly warmed-up lower midrange?).. but it's so well done and suits the overall tuning of the phone that I don't find it offensive in the slightest. If you've read any of my other posts, you'll notice I have a deep objection to midbass humps (of any quantity).. so for me to hear one in this phone and not find it objectionable in the least is a testament to how well it's tuned on the FXT90.
Like the bass, the mids sounded much more fleshed now that I have a deeper, more effective fit & seal. Separation between voices and instruments was more easily delineated for me when worn over-the-ear. The mids have a warm, natural, slightly liquid color to them. As I stated previously, the upper mids/lower treble was unnaturally fatiguing for me when worn "down." I don't know if this was because of in-ear resonance or something else.. but that spike has subsided greatly and I can rally appreciate the crisp sparkly of these phones now without the fatigue. Finally, the soundstage sounded complete. They always had good depth, but the width left a little something to be desired. With the deeper, more effective over-the-ear positioning, I got better isolation and sealing.. the soundstage width was much more apparent.. perfect in fact.
Despite the low impedance, they pair wonderfully with the mx-1. Everything tightens up, the soundstage improves, and the phones sound more controlled in general. I've been listening to most of my phones through the mx-1 a lot the past few weeks and it's truly a lovely amp.
So, what I've found is despite no needing a deep seat, play with how you wear them and you'll be surprised by how good these can sound.
