64 Audio U18t (U18 Tzar) - Universal IEM - Official Thread

The 64 Audio “U18t” (“U18 Tzar”) is the world’s first universal-fit earphone with 18 balanced armature drivers per ear (8x low, 8 mid, 1x tia mid and 1x tia high), using their new “tia” (tubeless in-ear audio) open drivers, “Apex” (Air Pressure Exchange) pressure (and fatigue) relieving vent, combined with a tuned acoustic enclosure.

These are are pitched as a reference monitor and have a neutral tuning to match that purpose. Their signature, primarily in the lowest registers, can be altered slightly by using different Apex modules (the little silver/grey plugs) - and both current M20 (more isolation, with neutral bass) and M15 (slightly less isolation, slightly elevated bass) modules are included.


At @prfallon69’s request, here are some high-level thoughts on the U18t, and per that request some commentary vs. CA Andromeda and Shure SE846 … ahead of a full review …

The U18t is the most tonally neutral (I’d say it’s actually neutral) of the four current universal-fit 64 Audio IEMs - especially with the M20 Apex module installed.

I’d generally consider the Andromeda to be largely neutral, also, provided those are driven out of a source with about a 1.5-2 ohm output-impedance. If your source for the Andromeda has a lower OI than that, then they’ll exhibit an elevated bass response - which won’t be the case with the U18t. The SE846, even with the “bright” filter, will also have a somewhat bassier (quantity) presentation than the U18t (I could never get the bass on the SE846 dialed down far enough on the SE846, which is why they became first a “fun” IEM and the ultimately I sold them). Using the M15 module in the U18t will bring the bottom end up to a level more satisfying for those that like a fuller bass response.

One of the first things you’re likely to notice, especially in comparison to the SE846, is the open and very spacious nature of the sound. That’ll be even more pronounced with the M15 Apex module installed.

The top end is extremely smooth and extended, and exhibits a similar type of “sparkle” and sense of “air” to that I found on the Andromeda. No sibilance or grain. Yet it is more than capable of the necessary bite for brass etc.

Detail/resolution, across the spectrum, is as good as I’ve heard in the IEM world and is ahead of both the CA and Shure models. Bass-resolution/texture is still the forté of, well, the tia Fourté (and Trió), but it is excellent nonetheless and while not something that sticks out the way it does with the SE846, shines in relative terms compared to either Shure or Andromeda with more control and articulation.

Coherence is well ahead of the SE846, which I always felt had the bass notes somehow delayed beyond the leading edges of higher frequency components in the music. I never measured them to see if that was actually happening, but as impactful as the Shure’s bass is - it always felt a bit “slow” or “delayed”.

The even-handed, neutral, presentation means that the microscope-like detail rendering of the mids and highs are easy to hear directly, and in comparison to other IEMs. They are not overpowered by the bottom end nor lost to excessive treble energy. The only IEMs I’ve heard that are as good, balance wise, in this regard, are the EE Zeus XR (Adel) in “R” (reference) mode - but the U18t still manage to out resolve them.

I find the Apex system (or similar, like Adel) to be pretty much essential for long-term listening comfort for me now. I’ll be interested to see how you find it.

I think the U18t are excellent and, unless you want a very specific non-neutral signature are very hard not to like.

I’m currently trying to decide on a custom IEM. Since I have the tia Fourté already, I am thinking either A18t (which is essentially the U18t in CIEM form) or was dabbling with the idea of the N8 (warmer/darker/bassier). If I do the A18t they’d replace my current reference monitor (EE Zeus XRA), which is looking more and more likely.


Thank you very much for you thoughts. I too find the Shure SE846 to be a fun Iem and was my first serious in-ear. Though a little heavy on the bass I have tried to make it as bright as I could. In that regard I went with the white filter. Though still a bass oriented iem I found it still had decent detail and a enough as a whole to let me enjoy my music. Albeit in a more relaxed fashion.

With regards the Andromeda I fell in love with the high end straight away. It walks the line between silibance and resolution and detail extremely well. Upto now it’s been the best in-ear I’ve heard for my personal tastes. It surpasses the Shure 846 in every every department except possibly the bass. Though the Andromeda’s have perhaps a more detailed bass it’s certainly not as fun. The analytical nature that some find that the Andromeda’s have, is to me one of its strengths. The Air and the soundstage that the Andromeda’s exhibit is also pleasing to my ears.

Overall they are two very different iem’s. They offer different listening experiences and will be keeping both in my collection.

With my acquisition of the U18t I am hoping to get another setup from these two. I am very excited and can’t wait to have them in my hands. It’s going to be a nice little project and I look forward to giving my thoughts on them. Well I’ll do my best anyhow.


Thanks for your initial impressions on the U18t @Torq! Have you tried the U12t? If yes, how does the U18t compare to the U12t? I own the U12t and was wondering how different they are… Thanks in advance.


I have!

In fact I had the entire 64 Audio universal line-up in my hands (and ears) for review very recently …

I just haven’t had time to get all of my listening notes written up formally and posted as reviews. I’ll create an official thread and post something along the lines of what I did above for the U18t sometime tomorrow (I’d so it now, but it’s more than I want to type on an iPad).

But, there are many similar traits between the U12t and the U18t, with the biggest differences being in the tuning … where the U12t have a much more bass-tilted presentation/significantly less treble presence. Which will better suit those that are treble-sensitive/bass-happy.

But, proper thoughts to follow in a dedicated thread …


I thought the Tia Forte and Andromeda had way too much treble quantity for my tastes. Is the U18t in the same ballpark, or has the quantity been tamed a bit?

The tia Fourte has an elevated treble level when compared to the U18t. Switching from SpinFit CP240 to CP500 tips leveled that out a bit. The U18t I would describe as neutral. So, no it doesn’t have the treble emphasis that I hear with the tia Fourte.

With the right source, Andromeda is largely neutral too. To low an OI and it gets overly bassy, too high and it goes the other way (though perhaps not to quite the same extent). So a comparison there is dependent on how the Andromeda were being driven.

At right about 2 ohms OI, I would say the Andromeda has a little more treble energy than the U18t, for a slightly less-neutral presentation. However, I would also say that the smoother and more refined top-end on the U18t means that it draws less attention to itself in that regard as well.


Dedicated thread for the U12t created here.

Some high-level thoughts from my extensive listening to them to follow there when I get a chance, probably a bit later today (trying to avoid more iPad-basd typing than necessary).


Thanks for another helpful and insightful response. So as someone who does enjoy the sound signature and overall tonality of the U12t, do you think that upgrading to the U18t is going to be a disappointment? Putting it the other way, would you recommend such upgrade or is that going to be a classic case of diminishing returns at its best?

I haven’t had a chance to make a more coherent and complete post on the U12t yet, so apologies for that.

In the meantime, I would say that from a technicalities perspective the U18t is a noticeable improvement over the U12t.

For example, bass hits harder on the U18t (dynamics, impact/slam) and has better texture even though it is at a lower level (quantity) vs the U12t. Which is to say that if you used EQ to equalize the frequency response for both IEMs, the U18t would have the superior bass performance (and, indeed, superior performance across the board).

At the same time, coming straight off the U12t the U18t is going to seem somewhat bright and lean by comparison. Go the other way and the U12t sounds rather bassy and a somewhat dark.

If you have a good EQ capability, and don’t mind using it, you could approximate the FR of the U12t so you could gain the better technicalities of the U18t and retain the tonal profile of the U12t. I can’t say if that’s a good way for you to go, however.

Which Apex module are you using in your U12t?


Thanks again for your reply. I don’t use EQ at all, I like to listen to music as the producer/artist intended (or try to get as close as possible) even though some of the audio gear I own tend to color the sound. I use the M15 module because I find the M20 module narrowing everything down while significantly increasing the bass response, which is too much for my taste (as I get older lol). Now you made me want to try the U18t… This hobby is preventing me from becoming wealthy. Lol

Thanks again @Torq


Hi guys, yesterday was my 50th Birthday so with that in mind over the last couple of months I have been selling off some gear. Gear that I no longer used enough to justify keeping or gear that I didn’t use at all anymore. Long story short I have been after some 64 Audio iem’s for a long time now. I contacted my favourite headphone store you know the one, Headphone.com. And I am now the proud owner of the 64 Audio U18t IEM. I’ve only had them a little over a day so won’t give any impressions yet. I shall digest their audio goodness over the next month or so before putting up a review.


Congrats! And Happy Birthday!!!


Congratulations and Happy Birthday!!

I hope you enjoy those as much as I did! Looking forward to your impressions/review!!


Congratulations and Happy Birthday!


Thank you everybody. I had a great day with my family. I am really enjoying these iem’s. They’re everything I wanted, but I won’t get carried away at this early stage. Again thank you everyone for your good wishes.:grin::hugs:


Just a quick update regarding my impressions and review. Unfortunately I have been suffering with a Sinus infection for the last 3 1/2 weeks. This has somewhat put everything on hold. As you can imagine I’m not getting much in the way of quality from anything I stick in or on my ears at the moment. I am improving so hopefully I shall soon be able to get back to some serious listening. Have a great day everyone.


Sorry to hear and I hope you have a quick recovery!


Get well soon. I had one recently as well. 5 days of migraine level headaches and stuffy ears.


Thanks guys, Antibiotics are clearing it up.

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