Just got the UM3x. I'm getting the JH13 eventually but in the meanwhile I thought I'd mess around with something more down-to-earth.
First impressions:
Extremely comfortable. Same as the UM2. Easily the most comfortable universal-fit IEM out there along with the UM2. I'm using the short comply tips now for lack of anything better.
Sound is mellow and polite but fairly rich. I don't really like the bass - it lacks extension and there's something wrong with its tone. Maybe it's the tips I'm using, but the SE530 definitely has better bass when it's fitting well. So does the W3. But on the plus side the bass is reasonably well controlled and detailed, you can follow basslines easily even if they do sound a bit off.
The mids are pretty forward, like they are on the Stax SR-001. They're also really good. Nice tone, good clarity, fairly but not overly fluid, and they have texture - quite a bit better rendition of texture than SE530 or W3, but not as good as the ES2 or SR-001. Still, it's the first universal-fit IEM I've heard that is actually capable of resolving texture. Vocals and midrange-heavy instruments are rendered very accurately. I like the mids more than W3 and SE530 personally, they remind me of the SR-001 mids a lot and that's only a good thing.
The highs are detailed but recessed. They have extension but they're far back in the mix and have no sparkle. Cymbals have shimmer and decay but sound like they're next door. This is less of an issue at high volumes, but at lower volumes the highs sound muted. On the upside, there's no harshness whatsoever. This could also be the tips, comply tips are notorious for muting highs.
Detail is good, but this is a headphone that tries its best not to sound detailed. Still it's all there, and detail is a notch above the W3 and quite a few notches above the SE530. It's quick, too, and doesn't lose definition as things become more complex. Dynamic range is also pretty good but I've never heard a BA canalphone that didn't have good dynamic range. The UM3x is on the mellow side compared to other BA canalphones but it doesn't sound dull at all.
Soundstage is good for an IEM. Everything sounds open, instrument separation is good, and imaging is precise. A notch above the W3 I would say and on par with the SE530. Same sense of air, but the UM3x sounds fuller.
On the whole it really reminds me of a more laid-back and mellow SR-001, though the bass is unfortunately nowhere near as good (and of course it doesn't have the electrostatic speed or air). This is right out of the box, no messing with eartips, no fussing with fit.
I've read comparisons between this and the ES2, and it's a bit like the ES2, but is also different. The ES2 is really forward and very vibrant sounding. The UM3x is mellow and more laid-back. But there is a similar sense of refinement that does beyond the W3 and well beyond the SE530, and both have transparent mids with very good texture.
But the best part of the UM3x, at least out of the box, is not the sound but the fit and overall ease of use. In order to get the W3 and SE530 to sound good I had to resort to torturously uncomfortable fit, and without it they sounded unlistebale. But the UM3x sounds good right out of the box and is comfortable at the same time. It basically does exactly what a universal-fit IEM is supposed to do but somehow never really did all that well - be comfortable, isolating, portable, and good-sounding all in one. So it's a keeper, at least for now.
This is also what the W3 should have been, once again mostly because of the fit. I really can't expect a casual listener to put in the kind of time and effort it takes to get the W3 to fit right and sound good if they're not lucky and have a good fit right out of the box. Now, maybe I'm just lucky with the UM3x and wasn't lucky with the W3 and SE530, but somehow I don't think so. The UM2 was not very fussy when it comes to fit either, and there is no reason why the UM3x shouldn't be the same.
