• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

64 Audio U12t Review (IEM)

Rate this IEM:

  • 1. Poor (headless panther)

    Votes: 34 15.8%
  • 2. Not terrible (postman panther)

    Votes: 63 29.3%
  • 3. Fine (happy panther)

    Votes: 79 36.7%
  • 4. Great (golfing panther)

    Votes: 39 18.1%

  • Total voters
    215
Crinacle has tested and ranked nearly 1000 IEMs.

He puts these in 2nd place, 300 or so places above the Fiio FD5 that Amir seems to think are great. Crinacle is the most respected IEM reviewer on the planet at the moment.

I wouldn't particularly value his opinion on which DAC or speakers to buy, but there's something not right here.

Crinacle's ratings are based on his personal views on tonality and he is not a supporter of the Harman target.
Regardless of the amount of experience one person has on a topic, an opinion based on personal subjective preference is no more or less trustworthy than any other opinion.
 
Rough guide:


BoM is one thing, but somewhere along the line there's operating costs - R&D, marketing, sales, etc.

Good on you for knowing how much something costs, if you think you can do better and still operate at a profit, then go prove it. I'm not defending 64 Audio, I just think actions are better than words... look at JohnYang1997, there's an example.
Think you guys are entirely missing the point I am making.

Those prices you quoted are not what they paid for the drivers. That is a retail offering.

If I think I can do better? Never implied that I could, NOR would I want to.
I simply think $2,000 is WAY more than they are worth.
They can be manufactured for far less, AND still have a healthy profit.


If they Must sell them at $2,000 to make a profit, there is something severely wrong with their business model......I think that should be VERY obvious.
 
This IEM likely sounds better than graphs here suggest, but it's not Amits fault. It's a closer match to USound, a target that is better for reasons discussed elsewhere but not as standardized as Harman IE.

Crinacle has tested and ranked nearly 1000 IEMs.

He puts these in 2nd place, 300 or so places above the Fiio FD5 that Amir seems to think are great. Crinacle is the most respected IEM reviewer on the planet at the moment.

I wouldn't particularly value his opinion on which DAC or speakers to buy, but there's something not right here.

Agreed.
 
Last edited:
Crinacle's ratings are based on his personal views on tonality and he is not a supporter of the Harman target.
Regardless of the amount of experience one person has on a topic, an opinion based on personal subjective preference is no more or less trustworthy than any other opinion.

There are good reasons to be far more dubious of the Harman target with IEMs than headphones, and more dubious with headphones than speakers.

Extra data points are fine, and no-one has to agree with Crinacle about everything or indeed anything.

But when practically every respectable reviewer (ALL of whom test FR, and all of whom have tested hundreds of IEMs) say that something is top-tier and Amir goes "meh" then it seems more likely that Amir perhaps has such a bias towards a target which is if highly dubious value with IEMs that perhaps his listening tests conform purely to his expectations.

His FR test results don't exactly line up with everyone else's either. Crinacle has tested 4 samples with relatively small variation and none of them show the steep dropoff after 5k that Amir's does.

For a large body of FR reviews data (15 separate reviewers) with personal targets and hundreds of tested IEMS check out the link select the different reviewer from the dropdown menu at the top: https://squig.link/?share=Super_Review_Target,64_Audio_U12t_(m15)

They all show a FR that looks a lot closer to Crinacle's than Amir's does. When we have a large number of test results and opinions and Amir is the outlier? Amir is the noob in this field. Doesn't mean he's wrong, but he's very confidently stepping out of his area of expertise.
 
For a large body of FR reviews data (15 separate reviewers) with personal targets and hundreds of tested IEMS check out the link select the different reviewer from the dropdown menu at the top: https://squig.link/?share=Super_Review_Target,64_Audio_U12t_(m15)

They all show a FR that looks a lot closer to Crinacle's than Amir's does. When we have a large number of test results and opinions and Amir is the outlier? Amir is the noob in this field. Doesn't mean he's wrong, but he's very confidently stepping out of his area of expertise.
Probably because of using a different coupler. I wouldn't make a big deal out of that.
 
Lastly, can we please stop with these super low impedances? Phones and phone dongles are not weak anymore, we don't need things sensitive to this degree..

Why do you absolutely want to drain your battery faster than it needs to?
 
There are good reasons to be far more dubious of the Harman target with IEMs than headphones, and more dubious with headphones than speakers.

[...]

Amir is the noob in this field. Doesn't mean he's wrong, but he's very confidently stepping out of his area of expertise.
I will reiterate: An opinion based on a singular subjective preference is not worth more or less than any other opinion regardless of experience. The Harman target is still the best publicly available approximation based on actual research data. If someone has a better target which can be consistently shown to achieve better results, I would be quite happy to see that data.

The particularities and reliability of measurements are explained in Amir's posts:
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!

There still could be something wrong with the measurement protocol or the unit that was measured. But implying blatant incompetence based on that is something I find a bit distasteful.
 
So the measurements are inexact, and they are not the same as a number of other measurements of the same IEM, but deviation based on those potentially flawed measurements to "the best but not very good" target available is the correct basis for reaching a recommendation?

And it's not a singular subjective preference, you really don't place any weight on the most highly regarded individual reviewer on the planet? His opinion is worth exactly the same as anyone else?

Also it not a single dissenting opinion - it is a collection of experienced reviewers (all of whom use objective measurements, and are significantly more experienced than Amir) and noting that Amir is the outlier.

I do not believe that Amir is incompetent, and I never said that he was.
 
Last edited by a moderator:
So the measurements are inexact, and they are not the same as a number of other measurements of the same IEM, but deviation based on those potentially flawed measurements to "the best but not very good" target available is the correct basis for reaching a recommendation?

And it's not a singular subjective preference, you really don't place any weight on the most highly regarded individual reviewer on the planet? His opinion is worth exactly the same as anyone else?

Also it not a single dissenting opinion - it is a collection of experienced reviewers (all of whom use objective measurements, and are significantly more experienced than Amir) and noting that Amir is the outlier.

I do not believe that Amir is incompetent, and I never said that he was.
I think you misunderstand what measurements represent and how they work. To quote Amir again:
As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests.
I also think you misunderstand what the Harman target represents. It's the result of a statistical evaluation. Statistics are inherently not extremely exact. There is still a lot of valuable information contained in properly gathered and evaluated data.
Does that mean the Harman target is perfect? No. Does that mean the Harman target is worthless? Also no. It is simply the best target that currently is publicly available. Once again, if there is a better target that can be shown to be consistently higher rated than the Harman target, I would be quite happy to see that data.
In the meantime the Harman target is the best approximation currently available and testing against any target is better than testing against none.

If you look at the research you will find that experience plays no role in preference ratings:

To re-iterate again: No one subjective evaluation is worth more than another. That includes both Amir and Crinacle and [insert any reviewer].
 
But when practically every respectable reviewer (ALL of whom test FR, and all of whom have tested hundreds of IEMs) say that something is top-tier and Amir goes "meh" then it seems more likely that Amir perhaps has such a bias towards a target which is if highly dubious value with IEMs that perhaps his listening tests conform purely to his expectations.
I did not give it "meh" rating. I gave it good rating. It's high distortion which others don't measure was a major negative especially in this price bracket.

As to most people praising them, that is the norm with expensive audio products regardless of performance.
 
Why do you absolutely want to drain your battery faster than it needs to?

Because I'd rather not have to be stuck between two volume settings (iPhone sucks balls), and also I'd like to actually use some of the output power available and not feel like digital volume being so low and having that contribute to crushed SNR. But mostly, low impedances are scary, many times I've had loud content play on IEMs because it was 4/16 volume level set.

They can make the IEM sensitive, but I'd rather have higher impedance. Nothing less than 50, and more preferably something like 100. I hear this is trivial to do in design when making audio products, and it's mostly a decision, and not some sort of technical barrier or something that would -impede- performance.

How do you define "interesting engineering"? I can agree that many products are saturated that can also be said for many other types of product in audio. If it isn't tuned to a certain target you will say it's wild and unrefined, and if it's tuned to your preferred target you will say there's nothing new. What is your expectation for something interesting but also works well?

As saturated as the IEMs market goes, 64audio still has a few unique designs to have an edge over other competitors, for example their apex module (many IEMs don't even have module or bass/treble switch).

Talking about ergonomic, I think we figured out what fits the easiest for most people a long time ago, I just don't know why certain IEMs company don't go for that. Maybe it has something to do with their design aspects. Also low impedance fits well for many sources, I don't know what are the benefits of increasing impedance over the current setting.

I think IEMs are in a good spot right now but I really hate the pricing of many "TOTL" IEMs in recent years. I also wish they would stop hyping up (overpriced) IEMs cable as if they are some sort of a mythical improvement for transducers.
Tuning is irrelevant in totality of ergonomics aren't on point in my view. This goes for both headphones and IEMs.

As far as what's "interesting", it would simply be something novel, or against the grain with respect to features provided. Usually when a feature that isn't provided commonly is present within a product, that's an example of interesting engineering as it requires more effort than not when including said feature.

As far as 64 audio, they should worry more about their cables, and the pointless use of tons of drivers before they start adding bass switches (which isn't novel, it's been done by other IEMs in some form or another at the high end).

As far as ergonomics, they don't change anything because they don't want to bite the bullet on the cost with respect to R&D, nor paying for proprietary tip designs. Also tuning is seemingly easier with a straight tube going right in your ear that can be rotated as it's all a circle. To go oval, you have to have confidence your ergo's make sense. Their priorities are skewed unfortunately.

IEM's are in a boring place in terms of design (full metal IEM's are stupidity btw, heavy for no reason, and are prone to condensation that can damage/corrode some, while others suffer SPL issues after meshes get humidity forming on them when you take a metal IEM from listening outside, and setting inside a nicely warm room). The prices don't make sense from a value perspective in the slightest. They're literally testing the waters with how far they can push it without doing any work that remotely reflects the production cost. Any IEM costing more than what Meze put out doesn't really make sense to me. So anything universal around the cost of $1000 is about the limit (no IEM was better finished than that one). Unfortunately that IEM supposedly had bad tuning (the stem is hilariously massive and would be a nightmare to keep clean with no filter for some stupid reason), are made of metal thus heavy, and also like virtually every other IEM maker (aside from folks like SONY or Sennheiser that do their own designs and contract truly custom cables for their products), they all use cables that can be picked up pretty easily on AliExpress for a fraction of the cost. These ridiculous multi-weave multi-core "OFC" cables are all seemingly made by a source or two, don't really use some form of rubber jacket (instead use these stupid clear-view plastics) and weigh more than they have any right to. Some have a weave so thick, that the earhook area forms hotspots on the ear. Pair that up with a generally heavy-for-no-reason metal IEM, and you have the current crop of silliness.

So tbh, I think IEM's are in a horrible spot. There are a few nice ones. Most perform well enough. But it's just weird seeing the only movement come out of non-audio companies like Samsung and Apple (and Sony recently with their open ring IEM of sorts). Everything else on the market is just aesthetic pandering. Like you say, the hype makes no sense, nor does the cable worship. For headphones you have people using paracord to build custom cables. I cannot fathom on anyone can tolerate such material given how great the microphonic effects are (not audio microphonics, but actual microphonics that occur as a cable rubs your shirt or whatever). I see Sennheiser also doing this stupidity when offering their more expensive XLR cables for the HD800 for example. I'd literally pay them more money if they could just get rid of the paracord and make the cable as basic, soft, supple, and plyable as their HD600 line (you know, the cable that costs less than $20 if I recall).

Just makes no sense to me. This market makes one scratch their heads.
 
Last edited:
As to most people praising them, that is the norm with expensive audio products regardless of performance.

That is true in general, but possibly less so with IEM reviews; certainly Crinacle and many other of the most well known reviewers are not averse to marking down far more expensive IEMs than these. There are IEMs on Crinacle's list hundreds of positions lower on his overall rankings that cost far more. One of his lowest ranked IEMs has a $7,000 price tag, and he described a $10,000 set as "An indescribable affront to God and humanity both in sound and pricing."

[Edit: The fact that you would casually make that assertion in the specialised IEM review space shows that you are very much out of your comfort zone here.]

I would be very interested in hearing a conversation between you and Crinacle actually, I imagine I am not alone in that. Topics like the Harmon curve, the state of IEMs, etc. would all make for very interesting discussion. The two of you are quite possibly the most respected audio reviewers at the moment. Just a thought. :)

Please note (notwithstanding my puzzlement over this particular review) - IMO you are one of the most important people operating in the audio community at the moment. Your reviews and opinions are as fact-based as you can make them, you have invested large amounts of your own time and money, are knowledgeable and certainly as far as I can tell are operating in good faith and entirely honest and decent person and doing a great service to all of us, and I certainly appreciate it very much.
 
Last edited by a moderator:
Because I'd rather not have to be stuck between two volume settings (iPhone sucks balls), and also I'd like to actually use some of the output power available and not feel like digital volume being so low and having that contribute to crushed SNR. But mostly, low impedances are scary, many times I've had loud content play on IEMs because it was 4/16 volume level set.

They can make the IEM sensitive, but I'd rather have higher impedance. Nothing less than 50, and more preferably something like 100. I hear this is trivial to do in design when making audio products, and it's mostly a decision, and not some sort of technical barrier or something that would -impede- performance.


Tuning is irrelevant in totality of ergonomics aren't on point in my view. This goes for both headphones and IEMs.

As far as what's "interesting", it would simply be something novel, or against the grain with respect to features provided. Usually when a feature that isn't provided commonly is present within a product, that's an example of interesting engineering as it requires more effort than not when including said feature.

As far as 64 audio, they should worry more about their cables, and the pointless use of tons of drivers before they start adding bass switches (which isn't novel, it's been done by other IEMs in some form or another at the high end).

As far as ergonomics, they don't change anything because they don't want to bite the bullet on the cost with respect to R&D, nor paying for proprietary tip designs. Also tuning is seemingly easier with a straight tube going right in your ear that can be rotated as it's all a circle. To go oval, you have to have confidence your ergo's make sense. Their priorities are skewed unfortunately.

IEM's are in a boring place in terms of design (full metal IEM's are stupidity btw, heavy for no reason, and are prone to condensation that can damage/corrode some, while others suffer SPL issues after meshes get humidity forming on them when you take a metal IEM from listening outside, and setting inside a nicely warm room). The prices don't make sense from a value perspective in the slightest. They're literally testing the waters with how far they can push it without doing any work that remotely reflects the production cost. Any IEM costing more than what Meze put out doesn't really make sense to me. So anything universal around the cost of $1000 is about the limit (no IEM was better finished than that one). Unfortunately that IEM supposedly had bad tuning (the stem is hilariously massive and would be a nightmare to keep clean with no filter for some stupid reason), are made of metal thus heavy, and also like virtually every other IEM maker (aside from folks like SONY or Sennheiser that do their own designs and contract truly custom cables for their products), they all use cables that can be picked up pretty easily on AliExpress for a fraction of the cost. These ridiculous multi-weave multi-core "OFC" cables are all seemingly made by a source or two, don't really use some form of rubber jacket (instead use these stupid clear-view plastics) and weigh more than they have any right to. Some have a weave so thick, that the earhook area forms hotspots on the ear. Pair that up with a generally heavy-for-no-reason metal IEM, and you have the current crop of silliness.

So tbh, I think IEM's are in a horrible spot. There are a few nice ones. Most perform well enough. But it's just weird seeing the only movement come out of non-audio companies like Samsung and Apple (and Sony recently with their open ring IEM of sorts). Everything else on the market is just aesthetic pandering. Like you say, the hype makes no sense, nor does the cable worship. For headphones you have people using paracord to build custom cables. I cannot fathom on anyone can tolerate such material given how great the microphonic effects are (not audio microphonics, but actual microphonics that occur as a cable rubs your shirt or whatever). I see Sennheiser also doing this stupidity when offering their more expensive XLR cables for the HD800 for example. I'd literally pay them more money if they could just get rid of the paracord and make the cable as basic, soft, supple, and plyable as their HD600 line (you know, the cable that costs less than $20 if I recall).

Just makes no sense to me. This market makes one scratch their heads.
Wow, quite a rant... I totally may understand some of your critics as justified, on this particular product, but dismissing the whole IEMs market, frankly? It's an extremely alive segment, True wireless are everywhere at many prices, fidelity for decent price is more available than ever, IEMs are everywhere look around! All that gripe because everybody is using round sillicon tips that have been proven to work well? Me I am amazed every day that you could get this level of fidelity and bass reproduction out of drivers this size. Not everybody need to reinvent the wheel. Musicians have been using these types of earhook style assembly and multi drivers for years and keep buying them, for a good reason, if you pull one off it don't fall on your guitar, not everybody needs the same features. Not all manufacturers design stuff for you specifically.
You make this sound as Apple are the greatest of the great, just because they use Oval tips? Did you actually listen to their earpods? They are certainly not the pinacle of hifi... try them, listen to them, compare them... This site is about fidelity and the IEM market has reached height in fidelity that did not seem in the scope of what was possible just 10 years ago and still you complain because eartips are round shaped... that's silicon, or memory material... I can assure you the are not round anymore once inserted, that's beauty of it.... What about driver material design and materials, that develops at lightning speed with performance to boot. You are some tough to please client!
 
Last edited:
I did not give it "meh" rating. I gave it good rating. It's high distortion which others don't measure was a major negative especially in this price bracket.

As to most people praising them, that is the norm with expensive audio products regardless of performance.
I never got the mindset of how some defend really high prices......Good performance can come at Reasonable prices.

High prices are not a guarantee of good performance, NOR that the item is very expensive to make.
 
Crinacle's ratings are based on his personal views on tonality and he is not a supporter of the Harman target.
Regardless of the amount of experience one person has on a topic, an opinion based on personal subjective preference is no more or less trustworthy than any other opinion.

Not just Crinnacle, this IEM seems to have the most agreement amongst the respected reviewers as being the overall 'best' - guys like Resolve and I believe Precog might as well.

That said, agreed with this notion in general. This IEM for some reason has stood the test of time as having a fairly lofty rating with the Head-fi set. Sorta like the JH-13 did circa 2010 for a few years.
 
Not just Crinnacle, this IEM seems to have the most agreement amongst the respected reviewers as being the overall 'best' - guys like Resolve and I believe Precog might as well.
So you and they think the best IEM should have that much distortion? And its response curve is the ideal?
 
Its not the Hygiene per say.
IEM's as I see them are a very personal thing. like a razor, Toothbrush, underwear or socks.

A modern equivalent would be an electronic cigarette. It just seems odd to share.
image.jpg

In my defense, she was naked so I did not want to be rude.
He should be fine as long as he is wearing a mask while listening.
 
I've never heard these, just saying this seems to be the sentiment.
So I am supposed to agree with what the others say, damn the data, my experience and my listening tests? You have any research that backs accuracy of the consensus of reviewers as you state? This is how reviewers did in speaker listening tests:

ListenerPerformance.jpg
 
Back
Top Bottom