Review: 64 Audio U18t (with lots of comparisons including Andromeda, Ara, og Solaris and more)

I don't know. I feel like "not that fun" isn't an unfair criticism leveled at any IEM that tries to go for as diffused neutral as possible, especially because BAs pretty much have the same response speed and the difference in staging isn't nearly as apparent as among big cans. The Solaris definitely has a bit more "bite" to its signature and I can see why @rhythmdevils would prefer that. I like the Solaris a lot, but the shape doesn't really agree with my ears, and there is no Solaris CIEM.

I don't think I've ever used the stock tips on the U18t but they sound completely muffled and boomy on complys, which is why I suspect that the choice of the tips might have something to do with it. That and playing around with the output impedance a little.

 

It is not. Every 64 Audio IEM has peaks past the 10k region because of their topless BA supertweeters.

Of course, some people won't be able to hear this at all due to age or hearing loss, but as someone who can, I find the U18t incredibly sibilant, doubly so with the Sedna tips shown in the OP. Was extremely surprised when I read them described as dark of all things.
Personally speaking I find the U18t (and the other 64 flagship, the Fourte) to be extremely wonky sounding, in part due to to how sibilant and sharp it is, and in part due to the bloated bass rise and the strange pinna slope. Not a big fan, but for very different reasons to rhythmdevils.

 

Haha. I don’t really know what to say. I’m just laughing at being accused of having hearing loss and not hearing peaky treble. And preferring a “fun” peaky signature. Wow. Obviously my hiatus from this hobby means some people don’t know my history at all. I’m kind of the whistle blower on the treble issues plaguing almost all headphones. No one talked about that when I was new to head-fi it was all full of reviews about PRAT and “musicality”. I waged a kind of information war spreading awareness about the treble peaks in all headphones and the fact that bright and bass light was not neutral. Until @purr1n blew it wide open with objective proof of what I’d been hearing snd saying the whole time with his CSD plots.

I can confidently rule out my hearing There’s years of documentation of me accurately predicting FR and CSD measurements.

I also have pretty extensive experience with eartips at this point. I own 4 gallon sized zip lock bags full of eartips. I don’t use foam tips they sound like muffled garbage. The tips I used are actually some of the brightest and most resolving on the market due to their huge bore and length along with how they fit.

So I can also confidently rule out ear tips.

That leaves us with output impedance, your hearing and a possible set of fake u18t’s.

It’s more likely for you to not hear peaks than to hear peaks that aren’t there so this seems unlikely to me esp with two people saying it even if you’re a noob or even a boob.

I EQ’d them to be neutral which required about the same increase to the upper midrange and treble as the CA iem’s (with zero output impedance source). I will force myself to listen to these f'ing things more with the an IeMatch adapter that increases output impedance to about 2 ohms and report back but I can say pretty confidently that they will not be made bright or peaky by 2ohm output impedance. This U18t is pretty even but shelved in the treble and also bassy.

So that probably leaves us with the idea that my pair are fakes. I’m skeptical of this from the get go just because of a long history on Changstsr of every time a headphone that people had raved about measured terribly it was always heralded as a bad unit. Literally every time. I remember @purr1n half seriously joking about how many “defective” headphones he got.

but entertaining the idea, I bought them used on eBay late at night on a questionable decision that I could just sell them back snd not loose any money snd I wanted to hear a super resolving iem because I felt none of the iem’s I’d heard were as resolving as good orthos which came as a surprise. The seller said he bought them new just to review them so they were basically brand new. And they look that way. That doesn’t sound like the typical scenario for getting a knock off depending on where he purchased them. Knock offs wouid typically be sold in bulk qualities and wouldn’t include all original packaging. The CA knock offs don’t come with original packaging. Here’s what mine came in.





That doesn’t look like a knock off to me. But for 3k who knows.

maybe there was a product revision? If the eBay seller was being honest and bought them new from a legit store then these are very new production U18t’s.

I’ll report back about my findings with the ieMatch adapter. I’ll also use them with the ieMatch output in the iFI Nano just to have another reference point. And I’ll contact the seller I bought them from and see if he will tell me where he bought them and maybe send a screenshot of proof.

I’m also happy to send them to @shotgunshane or possibly to @purr1n when he gets his measurement rig up and running. As long as I can sell them soon (clearly on eBay after this review).

iem’s are also just pretty weird IME. There are so many factors it’s not the same as full size headphones. I’ve had three different Ara’s here and they all sounded different. I guess it could be fitting them differently but I don’t know.

 

I edited my review with new information in italics.

 

Just to be clear, I'm not accusing anyone of having hearing loss. I'm just pointing out that the frequency of the peaks is very high, and it's certainly possible that someone older may simply not pick them up just due to age. There's nothing wrong with this. And honestly, even if you theoretically did have some sort of extreme hearing loss that prevented you from hearing past 10khz, the 6-8khz region is pretty damn elevated, and would at the minimum be perceived as bright in the mid-treble. I'm more inclined to believe the issue lies elsewhere.

One thing I think might be a potential cause is a defective unit. 64's QA is... not the best. I've had spotty units fresh out of the box from them before, and pretty entertaining measurements to go with it. Getting your unit measured might be useful.

 

I’d hear them

 

If they were fakes, Merry Christmas.

 

who said anything about fakes? This is a super rare non bright non wonky version that has an extremely high resale value.

 

So we've got one bassy, one peaky, and one pretty neutral up to 8-9k. I can most definitely hear 18k and I cannot detect any peak above 10k on them. The Fourte does have a ton of excess energy at over 10k, and that is not something I've experienced with either the U18t or the A18t. I do get a little bit of tampering down after 8k, but not something that would make them sound muffled.

Keep in mind that tips aren't going to sound the same on each pair of IEMs. It's not just about the diameter of the nozzle, but also the position at which a particular pair sits in your ears and how deep you can insert them. I don't think that you can generalize from experiencing one pair of tips on a particular IEM to another. Some of the old Shures and Westones sound best with complys, most IEMs don't. A lot of variables here.

For what it's worth, I'm first and foremost an IEM guy. My first pair of CIEMs was the UE 7pro all the way back in 2007, and it had the most drivers of any IEM on the market back then. I've made my own DIY CIEMs. And I'll be the first to point out that even the stuff I own can be pretty bad choices for most people. And I like the U18t enough to put money down for a custom pair (this was a special event discount, so a hair over $2,000).

If anything, the U18t/A18t has less bass than the Solaris, Andromeda and the Atlas (and a lot less than the Atlas). The Solaris isn't boomy but the DD responds less quickly than the A18t's BAs. Again, the measurements would seem to agree with this assessment, although IMO preference for BA bass vs. DD bass is a subjective issue.

I no longer have them but that's mostly because I find myself picking up the pairs with more weirdness (and no, you don't know treble energy unless you've tried the Fitear Titan), plus I got an chance to sell them to someone who had access to a refit from 64 Audio, so I figured I would never get better resale than that.

 

Do they really, though?

On bass alone, I think this matches up pretty well to how I hear all 3 IEMs. Andromeda is thicker but not as bassy, and Solaris OG just has less bass period. I don't think this alone is enough to make the U18t pure mud and mush, but it certainly does point to it having more than neutral bass (and lower mids, for the matter).

 

If 64 Audio is stupid enough to put a permanent desiccant can in their iem case who knows what’s going on here.



What, do they think it can absorb infinite amounts of moisture? Put it in a lake and it will become a desert? That thing absorbed all the moisture it could very soon after the seal to the case was first broken.

fits very well with all my sonic and physical observations of the design of this iem. Very ignorant attempt at fancy-ness.

 

Dude, seriously, look things up before you post something like this. This just makes you look bad. The travel case itself has a rubber seal and is meant to be a drying chamber used to pull moisture out of the IEMs, you replace the pack (or bake them in an oven) as needed. It is a thoughtful design for touring artists who regularly expose their monitors to sweat.

64 Audio sells the replacement packs on their website for $4 a pop. They also sell a larger case that will carry both the IEMs and an IEM vacuum that mounts two of the packets for a complete travel maintenance kit.

https://www.64audio.com/collections/maintenance-tools/products/small-dehumidifier

Not that they came up with the idea, this is Westone's monitor vault which has been a thing since the early 2000s. My ES3X and ES5 both came with one, and I used them religiously whenever I spent time in Hong Kong because of the crazy level of moisture.

 

Jesus aren’t you smart. I still don’t buy it. Do you know how much moisture is in the air? Those desiccant packs only work once for a sealed product. Once it’s opened to the air they quickly absorb all the moisture they can and do nothing more. So I guess you can maybe use them once if they arrive sealed and aren’t rendered useless by the time you get them into the case snd close it.

You’re starting to sound like a head-fier whose favorite toy is being attacked.

 

Nope. Don't leave the box open, and they'll last for about a week if you open it 2-3 times a day. They're good until all of the beads change color. And don't forget that someone had to put that pill in the vacuum pack at the factory, a little bit of exposure to air won't completely saturate the pill especially for one this large.

I get about 3-4 runs of each pill if I put them in the microwave at the lowest setting. At some point the beads stop returning to the original color, and then you need a fresh one. I also have airtight boxes for cameras that use the same idea, just with a much bigger desiccant insert. The big packs will be good for weeks if you don't open the box every day.

I already said that I like them and I regard them as among the highest performing all-BA IEMs. Anything wrong with that?

 

I don't know which APEX module was used for this test but I strongly suspect that the U18t is using the M20 module here (-20db of noise reduction). The APEX modules are progressively more bassy with more noise reduction. The M15 modules should come in the box and they are about -4db at 20hz.

https://www.64audio.com/collections/apex-modules

If you shift the U18t curve down 4db from 20hz, it comes in slightly under the Solaris and about 3db less than the Andromeda through most of the bass range. There is also the MX module which seems like -7 ish at 20hz to me. I think I prefer M15 though as MX pares down the bass far too much.

In any case, I am not a huge fan of IEMs that have user-selectable tuning because I like the idea of putting a single signature forward for the user to experience. But 64 Audio obviously has aspirations of selling to professional musicians, and controllable ambient is useful on tours especially because the modules also work on 64's earplugs.

Klaus has measurements of the U18t with the M15 modules and difference to the M20 here:

https://www.klauseulenbach.de/2019/08/20/frequency-response-64-audio-u12t-u18t-and-fourte-noir/

It shows what seems to be a more balanced bass profile on the M15 and about -2.5db relative to the M20 at 20hz. Feels like more to me though.

 

Objectively speaking, the M15 and M20 modules don't make any significant difference on 64 Audio IEMs.

For comparison, the Nio. Obviously not a 1:1 representation of the U18t, but Crinacle's site doesn't have measurements of the U18t in particular because he considered it too negligible to be worth a dataset. In any case, I have seen his measurements in person of other units and I have made my own measurements in the past of differences between the units on my personal U12t and A12t units, as well as A18s, Nio and U18t demo units.

Subjectively speaking, I would agree with you; the M20 module is slightly bassier and has a slightly closed in stage that I'm not the most fond of it with my U12t. But the point is that from a pure FR perspective, it would not be nearly enough to affect the comparison graph I posted earlier.

 

It is nonetheless rated at -4 at 20hz...which is pretty significant. I don't know where 64 got that number from, but it roughly matches with my experience with the A18t, in that the M20 has more bass and thicker lower mids that also affects the clarify of the IEMs in a bad way. Although it is interesting that Crinacle is getting ~1 db of difference whereas Klaus measures it at 2.5, which still feels a little too small.

Either way, I think that we agree that the M15 is the way to go for most 64 IEMs, unless you really want less bass in which case the MX cuts that range down even further.

 

It is rated as such, but the objective measurements don't show as such. I have tried similar measurements on the same coupler model that Crin uses and have gotten an essentially identical result in regards to the differences between M15 and M20 throughout 64's product range.

Now, I'd be the first person here to say that the measurements are far from a perfect representation of the perceived amount of bass, but my point from the start was that the measurements do not corroborate with the idea that the U18t is less bassy than either the Andro or the Solaris. And, personally speaking, I would say I hear more overall midbass from the U18t than either of those IEMs, especially the Solaris, which I never found particularly bassy.