So, when I first got into this whole IEM thing I had the chance to try the 64Audio U12T which was, and still is, regarded as one of the best endgame IEMs. But, a few days ago I had the chance to listen to them again, and oh boy has my opinion changed on them… Because this thing… It hurts. Now, when I first heard it 2 years ago I thought it was amazing, but after getting to hear more gear over time, and changing my listening habits - I’m a little bit confused as to how there aren’t more complaints about this set.
Let’s first take a look at the graph. So, everything actually looks pretty nice before we hit the vocal drop off and treble rocket - the bass is overall still neutral, but slightly warm leaning which adds body to instruments and vocals. Personally I would’ve liked a little less mid-bass for this type of signature since it’s not a basshead set and the only scenario I think that warrants and justifies mid-bass is when you’re slamming and rocking your brains out without caring about clarity and all that stuff. But the bass is perfectly fine, there’s no bloat, nice texture, speed, and separation. It still doesn’t have the feeling of physical air slamming like a dynamic driver, but the energy is pretty good, and definitely not wet-noodle bass like the IE200.
However, here is where things take a nose-dive. Where did the vocals go? Why is there a sudden scoop at 3K which is where vocals are supposed to be. This reminds of the IE200 where the midrange is recessed, but here the vocals are actually even more scooped than the IE200. The added mid-bass also doesn’t help since you’re just muddying the vocals even more - sure it sounds thicker now, but the mid-bass in this case can’t act to balance any brightness from the vocals because there are none, so it just sounds muffled and a bit congested since there’s no vocal energy and brightness to cut through the mud.
Now, the smartypants at 64 tried to work around this by instead adding more treble to give vocals a sense of shimmer and edge, but instead they just come off as too sharp because the added brightness is in the wrong region, so instead of making vocals feel open now it’s both congested AND they have trailing sharpness at the end of their notes. Don’t know how they managed to do that, but then again, 64 also released this monstrosity of a unit, so who knows - maybe they’re just 5head and we’re all idiots.
But, the worst part is the treble. I can somewhat overlook recessed vocals since I can just turn up the volume, however, scaling becomes impossible now because of the stabbing high-end. So it’s either too much treble, or recessed vocals - your pick of poison. The funny thing is the treble would’ve been fine since it’s actually pretty solid from 6 to 10K, but then they just had to add two huge peaks at 13 and 17K - and with everything added together it just becomes too much.
Maybe people didn’t notice this because either they listen at a lower volume, have some sort of hearing loss, or their libraries just show how is the right fit; since I also didn’t hear any noticeable treble issues on slower and laid back tracks like first love by Hikaru Utada, the most recent Father John misty album, and Big Thief. However it does become very evident on songs with higher dynamic contrast like pretty much any K-pop, J-pop, and J-rock stuff. I constantly had to adjust the volume between the quiet and loud parts which makes the U12T’s overall dynamics pretty sad for $2000.
That aside, the U12T does however excel at detail retrieval, note sharpness, and overall instrument layering and separation. I mean, I certainly hope so with 12 drivers and THAT much treble, but overall there was no smearing, and I could clearly pick out individual instruments and micro-nuances - probably the best I’ve heard in those departments. Imaging is also great, centred, not floaty, and notes are fast in attack, decay, as well as being very precise and sharp on impact.
Staging is a bit weird though because vocals and midrange are recessed so there’s no context for other sounds to create a sense of distance which results in a flat feeling stage. But the U12T does feel very open and wider than other IEMs, and it’s not like the vocals are behind the instruments, however there’s definitely less contrast or 3Dness between them. I guess the upside to this decision is that it feels more open and deeper, but again might just be psychoacoustics.
Overall, even though the U12T has top tier detail and layering I still wouldn’t pay $2000, or even $500 for it because of the scooped out vocals and fatiguing treble that ruins many highly dynamic songs. For its use case, which I’m assuming isn’t basshead related, the Variations and EJ07M are a way better option with actual fully extended and open vocals as well as smooth treble dynamics. And if you want more warmth then there’s also the RSV and HeyDay as well. But ya, kinda disappointing… I guess it has a “unique” tuning, but I’ll have to re-do my list for sure with new criterias.
Anyhow, thanks for reading!