64 Audio tia Fourté - Universal IEM - Official Thread

64 Audio’stia Fourté”, so named due to the drivers and configuration of the unit, was 64Audio’s first IEM release using their new “tia” (tubeless in-ear audio) open drivers, “Apex” (Air Pressure Exchange) pressure (and fatigue) relieving vent, combined with an tuned acoustic enclosure.

They combine two of the new “tia” drivers, one for the highs, one for the mid-range, a BA high-mid driver and a dynamic low-frequency driver, the outputs from which converge and mix in a specially tuned acoustic chamber (which is the part that makes creating a custom-fit version a challenge) to produce their sound. And that’s couple with the equivalent of the M20 Apex model, yielding -20 dB of environmental isolation and impressive bass delivery.

This is the spot to discuss them …


Hey Guys,

I got my 64 Audio Tia Fourte’s in today. I’m been listening to them all day, so I hope I can offer some further initial impressions vs. The very short ones I posted of all the 64 Audio universals the other day.

Pro’s: Amazing soundstage/imaging for a closed IEM. Very “3D.” Hyper Detailed top to bottom. Great Dynamics. Very comfortable.

Con’s: PRICE. The overall coherency of the bass/mids/treble. Treble could be too much for those sensitive to treble. Included accessories.

The packaging is pretty basic, but all that you need really. I guess they could have gone a bit more upmarket, but if that would have been reflected in the asking price, then I’m glad they kept it the way it is. The Hifiman RE2000 packaging (and this is Hifiman we are talking about) is more impressive, and even includes more tips. That is one thing I wish 64 Audio had done, more tips. Lots more. Included are single flange silicon tips in SML, and 64 Audios foam tips in SML. I’ve been going back and forth between the silicons and foam tips today, and the results have been pretty surprising. More on that later. The included cable is pretty bad in terms of ergonomics to be honest. I’d like to change to a different cable (currently using an LCDi4 cable I had lying around) at some point that is comfier and a bit less likely to get tangled. They also come with a neat little hard plastic case to keep them safe when you are travelling, which is great. So yeah, included accessories could be better, but there is enough to get you going.

In terms of tips, I prefer the sound of the 64 Audio foam tips with the Fourte. They take a tiny bit of the edge off the highs, whereas the silicon tips make the highs more pronounced. The Foams also seem to bring up the bass a tiny little bit, but there isn’t much difference. I find the silicon tips more comfortable, but the foam tips do sound better, so I will try to get used to the foams.

For my personal taste, the Fourte is a tiny bit bass light, but I mostly listen to electronica and do prefer a pretty robust bass response. I’ve tried bumping the bass up a couple db via EQ, and that brings the bass level more in line with my personal preferences. However, I could definitely listen to the Fourte without EQ, they aren’t bass light by any means. The bass on the Fourte seems really…textured? Lots of detail to it. Its certainly not a one note bass experience, and the sub bass is pleasant.

I can see the mids of the Fourte being a problem for some people in that they aren’t super lush and warm like a pair of LCD-2 or something similar. However, the mids are very detailed, and not sucked out sounding. They don’t sound hollow.

The Highs are both the Fourtes strongest point, and for some I would imagine their weakest point. There is a fair amount of treble. If you are treble sensitive, these would not be a good choice of earphone. There is so much air and space, and detail to the treble. It is really impressive.

The soundstage is the widest I have heard from a pair of closed back earphones. Not as wide as the LCDi4, but close. A tiny bit wider than the Hifiman RE2000, but with more depth. Very precise imaging.

I can see why some people don’t like these earphones, they definitely have some weaknesses. However, for my ears, their strong points are very strong. I definitely recommend giving Fourte a listen if you get the chance.


These seem just up my street. I like plenty of treble with plenty of air. Seems like these would be my end game iem’s. But that price though.


I think @ufospls2 is selling his pair … :wink:

I’m definitely keeping mine though. I expect they’ll be the next item I post a full review for too.

As a good example of how preferences play into these things, where @ufopls2 finds them a tiny bit bass light (and having chatted at length with him about many things I have a good idea where he likes his bass), I find the bass level very close to perfect for me. Any more and I’d be putting them into the “bass centric” or “basshead” category (the Campfire Audio Vega are, for example, a good bit bassier than the tia Fourté).

They’re certainly incredibly articulate and detailed in the lowest registers with excellent texture, impact and slam.

They’re definitely not neutral either. Bass and treble are both emphasized. The treble seems a bit more present than I think it actually is, perhaps due to the extreme resolution and detail they portray.

The EE Zeus XR in “R” mode are a much more neutral experience. Though they do not have anything like the low-end drive, impact or texture of the tia Fourté.

I’ve had them in my ears for 8 hours today (with SpinFit CP240 tips) and have experienced no fatigue or discomfort. As with ADEL on the legacy EE models, the APEX venting really seems to help in that regard (at the cost of some isolation).

I’d agree with @ufospls2 that, despite a number of extremely impressive technical traits, they’re not going to be for everyone. And not just because of how much they cost.


Thanks very much for your detailed thoughts. I am very much in love with the sound of my Andromeda’s but if I had plenty of disposable income (which at the moment I don’t have) these would be my first purchase iem wise.

1 Like

The Andromeda are a formidable IEM, for sure.

Given the right source (specifically something with about a 2 ohm output impedance) they’re more neutral than the tia Fourté (out of my primary player the bass tends to get away from them).

I just wish the nozzles were smaller than they’d put that Cerakote finish on all of them.


I auditioned them during the tour the ‘other’ place ran. Very nice indeed, I too am not a basshead and found them very appealing. What really hooked me was the detail throughout. I was also very impressed by the soundstage. The price? not so much. A week with them, and the U18t and I found I preferred the U18t but to be honest I just couldn’t put my finger on exactly why. I own the U4SE which surprisingly gets me 85% of the way to the TOTL models.
If I had the funds I’d probably be looking at the 18t much more seriously, as it is mortgage, kids, car payments takes precedence.

1 Like

I finally got my full review of the tia Fourté posted.

It’s a bit longer than usual - even for a flagship product - due to my wanting to cover the effects of the “Apex” system and some high-level thoughts on where they sit in 64 Audio’s overall line-up.


Being stuck “mobile” (or moving around more than I’d like, since it’s not for “pleasure” right now), and having just updated my selected of SpinFit tips to include all of their current models, I got around to trying the CP500 with the tia Fourté.

Very much an improvement over the CP240 I was using before. More even tonality, including a better match between bass and treble levels. Doesn’t make them neutral. In fact it brings the bass level up a bit, but that just makes it an actual “U” shape, rather than a specifically treble-tilted one, and it shallows the depth of that “U” as well.

I’ll attribute the difference to the shorted distance between the end of the tia Fourté’s bore and the exit of the ear-tip on the CP500 and the fact that the CP500 does not constrict the diameter of the bore’s output like the CP240 does (4.0mm on the CP240 vs. 5.25mm on the tia Fourté).

A bit more listening and I may have to make an update to my tia Fourté review. I loved them before. But this makes them even better.


Another few hours with the CP500 on the tia Fourté …

Two things come to mind …

First, 64 Audio really need to figure out how to make these in CIEM form (I’ll be happy to beta test, even if it costs me)! That’ll take all the variability out of this sort of thing.

Second, while I’ve long-since been aware that tip-rolling can have a significant effect on how one perceives a given IEM, I would not have suspected that a 1.5mm difference in bore diameter in a given tip would make this much difference.

Spinal-tap moment for these IEMs.

We are now at …



While waiting for something approaching “coherence” for various “attendings” …

A&K SP1000m -> tia Fourté (w/ SpinFit CP500), playing Yello’s “1980-1985 - The New Mix, in One Go” has been near-akin to a religious experience. Discovering nuances to this album I’d not experienced before, despite it’s relative musical coarseness.

And this goes back to my original “listening” which stemmed from a hastily-copied-from-early-CD-to-TDK “MA-R Type IV” cassette, and played back by a then state-of-the-art “barely-bigger-than-the-tape-including-a-pair-of-rechargable-AAAs” AIWA cassette player into Sony bass-port ear-buds …



I have a pair of the 64 Audio U18t’s on their way. Could you give me your thoughts on them please. Bearing in mind I’m a huge fan of the Andromeda’s and Shure SE846’s amongst others. Thanks.

1 Like

Sure … and I put it in a new thread dedicated to the U18t, just to focus the discussion.


Looking for a bit of help with tips for my Fourte Noir (understanding this isn’t a Noir-specific thread…don’t think there is one and didn’t think it was necessary to start a new one…moderators will correct me if needed!).
So, there’s a lot to love with the Noirs, but high frequencies can be a bit much for me, and sibilance can also be a problem.
I have noticed that the tips I use can make a significant difference…silicone tips are the worst for me (both those that came with the IEM and others, such as Final E tips); followed by the foam tips that 64 Audio supplies with the IEMs; comply foam tips are the best i’ve tried so far, but still not quite right.
I have several more tips on the way - namely from Symbio and Dekoni (I was considering Westone tips, as well, but I don’t believe the bore size will fit 64 Audio IEMs).
I know this sort of feedback on the Fourte/Fourte Noir is fairly common, but just wanted to see if anyone has other ear tip recommendations.

Thank you


Just wanted to bump this thread with my latest written review of the Tia Fourte: https://www.headphones.com/blogs/news/64-audio-tia-fourte-universal-iem-review-room-for-detail

General takeaway is this:

Detail - 9.5/10 (best in class)
Speed & Dynamics - 9/10
Stage & Imaging - 9.5/10
Timbre - 9/10
Tonality - 7.5/10

While not the typical audiophile tuning, the Fourte makes me think of a very specific room, and because of that I find this to be more of a tool for musicians than strictly an audiophile device. But with that said, it’s not hard to get into that kind of tuning, and if you do, you get to enjoy some of the best technical performance out there.


Once again, another killer review. I like the structure of your reviews, as well as your very well articulated way of putting your thoughts into words, this combo makes up for an easy and pleasant read. Thank you.

I own both U12t and Fourté (sold the Trio) and in the beginning I couldn’t stand the Fourte’s tuning and preferred the U12t 11 times out of 10 but after more careful listen (that’s probably brain burn-in), I find the U12t “dry, thin and boring” and the Fourte is my go to IEMs!

Interesting that you find the Fourté geared towards musicians instead of audiophiles, that’s exactly the opposite of what 64 Audio recommends - U12t and U18t for musicians due to its overall “neutrality” and Trio and Fourte for audiophiles due to their “fun” tuning. This is why there are no absolutes in this hobby, we all hear differently indeed!!


Yeah, it’s not the first time I’ve come across this either. The idea that “listeners want fun sound and the pro audio crowd want linear sound” might be what a general trend for what market research has told someone but likely isn’t all that accurate for us ‘serious audiophiles’. I also don’t think musicians would necessarily prefer the Fourte over the U12T either, but I can easily see certain musicians or pro audio types really being into it for its stage characteristics (that the U12T doesn’t have)


Great review, as usual!
I have never heard the Fourte, but owned a Noir (and have since sold it). While the Noir is tuned a bit differently than the Fourte, I found the treble to be unbearable from time to time (which is why I sold them). Shrill, overly-emphasized, with a significant presence of sibilance.
And my understanding is that the Noir is supposed to be a bit warmer overall than the Fourte!
Anyhow, I loved everything else about the Noir - dynamics, soundstage, detail, etc. But the tonality was a deal-breaker.


Here’s the video, sorry for the delay - the sun came up while filming so I had to reshoot everything haha. I think I’m the one person who gets annoyed at a nice bright sunny day.


Good review.

Thank the lord I am not a big IEM fan - between those and trying to increase other areas of my audio chain I would need one of those reverse mortgages. Currently I only need to skip a few payments to fund my wants.

I just cant see myself putting money towards something like that unless it had an incredible warranty as I have come across enough stories about driver failures and such in IEMs to put me off expensive purchases. I have no notion about 64 Audio’s reliability, maybe it’s stupendous, but the 1 year limited warranty is a bit of concern, perhaps unwarranted.

Ive seen some claim that a 2 year lifespan is what one should expect from IEMs!?!? Not sure what to make of that. Sounds like bull to me but it has stuck in my mind.