64 Audio U6t

I picked up a used pair of the U6t and they arrived a couple days ago, so these are my impressions after about 6-8 hours of listening to them (so take my opinions with a grain of salt).

As background, I am more of a headphone guy and this is only my third pair of IEMs (so take my opinions with a grain of salt).

I listened to them using either my iPhone with the apple dongle or with the FiiO Q5S. They are powered well off of the apple dongle and I didn't notice a difference. All of my listening has been with the m15 apex module.

These are fantastic IEMs for enjoying music. They provide an engaging and dynamic presentation, have a fantastic tonal balance, and come in a sleek and comfortable package. Their detail is not on the level of headphones like the Verite Closed or LCD-XC (I don’t have much IEM comparative experience), but to be frank it was good enough that I didn’t care one lick.

The soundstage was minimal, maybe slightly better than other IEMs I've heard. The instrument separation was quite good.

I didn't think that I'd like the aesthetic of the U6t (looks a little industrial), but I have to say that they are really sleek and more understated than I thought they would be.

The comfort on these is fantastic. The U6t only really touches my ears at the tips which sounds a little crazy, but ends up being incredibly comfortable. I will say that I tried jump-roping with these in and that wasn't a great experience.

The accessories are a solid set including a bunch of tips (6 pairs), a really nice cable (for a stock cable), a cleaning tool, a nice case, and the apex modules.

My crazy take: in my very limited experience I would say that the 64 Audio U6t is almost ZMF-like, as if the Eikon and Auteur had a baby and that baby was an IEM. The U6t hits hard, has fantastic timbre, and has an engaging and fun frequency response, though the bass doesn't rumble in the same way. That’s how I felt when I heard the the Auteur and Eikon and fell in love with ZMF and that’s how I feel right now with the U6t.

Comparisons:

Moondrop Blessing 2 (not dusk) - I really liked the Blessing 2 and it has some similarities to the U6t, especially in their strengths. More specifically, I think both IEMs excel in both excellent dynamics and timbre. The U6t is better in both, but if I was to compare the new price tags I would be disappointed in the only modest improvement. The frequency response is significantly more to my liking on the U6t. The bass and mids have better separation on the U6t and though both IEMs have a lot of treble energy, the U6t never feels bright to my ears. The U6t is smaller, sleeker, and way more comfortable than the Blessing 2 for my ears.

Thieaudio Oracle - I wanted to like the Oracle so badly (mostly because I love the aesthetic), but sadly, I found that the Oracle did not agree with me. Where the U6t is engaging and dynamic, I found the Oracle to be clinical and dead. Yes the Oracle was pretty detailed and sounded quite clean, but I rarely found myself lost in the music. The limpness of the impact on the Oracle as compared to the U6t (and Blessing 2) is a bad memory for me. Also the difference in treble is night and day and heavily leans to my preferences for the U6t. The U6t is smaller and way more comfortable than the Oracles for my ears, but I do love the look of the Oracle.

Overall I am really impressed the U6t and although I’ve only been listening for a short time, the honeymoon period (so far) has been memorable one. Only downside is that I’m now really intrigued to hear the U12t.

UPDATED ON NOV-18-22 — The U6t from 64 Audio aren’t new here. They were reviewed and eventually let go in the hunt for a single dynamic driver. With the hunt over, it is now time to revisit a dearly missed old friend.

Where a single dynamic driver (DD) makes sense in the pursuit of coherency and timbre — multiple balanced armatures (BAs) make sense as transducers of choice for something being so close to one’s ear canals. With that said, the closest multiple BAs get from replicating a dynamic drivers’ coherency and timbre, the better.


The object — Oozing understated class, the U6t are likely the sharpest-dressed IEMs of all 64 Audio’s lineup.

Small, light and comfortable, the U6t come with a no-nonsense newly upgraded 3.5 premium cable; three apex modules allowing to customise the isolation/tuning; a tip holder wheel — ever had an ear tip rolling and tumbling under barely accessible furniture? — and round leatherette case. The downsides? A scratch-prone epoxy faceplate and there’s no bundled mesh pocket.


Fit & Comfort — 64 Audio’s nozzles are on the thin and average-length side. To most, and certainly here, this means a high likelihood of comfort. The three types of bundled tips (Foam, Silicon and SpinFit) in S, M and L only strengthen the likelihood of getting a nice, comfortable, fit.

Worthy of note is the stock cable’s angled 2-Pin connectors ending up in an ergonomic curve of hard plastic which can be an issue for some ear shapes as it (slightly) was the case here.

64 Audio’s air pressure exchange (apex) modules essentially alleviates listening fatigue as the modules vent air pressure from what would otherwise be a sealed ear canal. Apex modules have different levels of isolation which breaks down as follow: M20 module (-20dB), M15 module (-15dB) and MX module (-10dB). The less isolation, the less pressure, the less impact different tips have, the more comfort, but also the more soundstage, detail and texture.

Tips used: settled on the SpinFit CP145


Sound — The U6t, with either the MX or M15 modules, are an organic, effortless and musical listen. With no hint of BA timbre, they are utterly enjoyable for short or long sessions alike.

The amount of lows will very much depend on the apex module in use. The default M15 module will offer plenty of both sub- and mid- bass while the MX module will highlight mid- rather than sub-bass.
Albeit more than adequate with the M15 module for an engaging listen, the MX module will highlight the U6t’s true capabilities in terms of mids, highs, soundstage and overall detail and texture.
All-in-all, regardless of the module used, the U6t stand out for their natural, organic, musicality and tone.

Files / Sources used: CD-quality FLAC bought from Qobuz & Tidal HiFi streaming / Sony NW-WM1AM2 (Direct Source: On), Cayin RU6 (NOS) and Astell & Kern SR25 MKII (Low Latency Slow)


Compared to Softears’ Twilight — While equally coherent, natural and lifelike, the U6ts are warmer and more intimate than the Twilight.

Overall, the Twilight are clearer than the U6t. Moving from the M15 to the MX module on the U6t gets them closer to the Twilight but it will be at the expense of the U6t’s sub-bass.

In terms of quantity, the Twilight’s sub-bass sits in-between the U6t’s M15 and MX modules. In terms of quality, the Twilight have the unmistakable physicality and timbre of a single DD IEM compared to the U6t which have an excellent low-end for an all-BA IEM.

The Twilight’s mids are more up-front and you’ll get more grit out of them than the U6t’s although the MX module will get them closer to the Twilight.

Highs feel a tad sparklier on the U6t, especially with the MX module, yet never get too hot. Paired with a bright source, the Twilight could be too much for some.

The Twilight have more detail and a bigger soundstage than the U6t with both the MX and M15 modules.

The U6t, however, can feel like they have more natural transients and texture.


Conclusion — The U6t are an amazing organic and effortlessly musical listen which is difficult to get tired of. In spite of their admittedly hefty “entry-level” price in 64 Audio’s lineup, they are recommended without hesitation as a blind buy for anyone who’s looking for an IEM to enjoy their music library without any reservation.