64audio U12t (12-BA) Review: TOTL All-Rounder

Introduction

Anyone who’s based out of the US knows the struggle of demoing high-end IEMs – or even IEMs in general – and my experience bears no exception. In fact, it was only by a stroke of luck that I got to listen to the U12t: I was doing a local transaction for another pair of IEMs, and the seller happened to own the U12t so he let me have a listen. 

With COVID-19 going on, my first listening session with the U12t basically took place in my car with the seller parked next to me. Certainly far from ideal, but in the first couple minutes I listened to the U12t, I was hooked. And I’m not exaggerating when I say that for just a moment I forgot I had IEMs on. So when the same seller put them up for sale a couple weeks later, well, I had to cop them. You can purchase them here for the cool price of $1999. While my initial hype has abated, make no mistake that the U12t are endgame-worthy IEMs. Let’s talk about why.

Disclaimer: I am an amateur audio enthusiast. I don’t have half the knowledge and lingo that some reviewers have, so forgive me for being blunt or ambiguous at times. These are my purely subjective thoughts, and I paid for this IEM with my own money. 

The Tangibles

The U12t comes in a large, cardboard box. Accessories include various tips, a hard-plastic case, M15/M20 Apex modules, a clip, and cleaning tool. It certainly doesn’t feel like you just bought $2000 IEMs, and the clear spelling error on the packaging is just the icing on the cake. 

Build quality of the IEMs is good. I bought mine second hand, so I’ll refrain from commenting much here. However, a clear weak point of the IEMs is the lack of a recession point for the cable pin. The left side on my U12t experienced audio cutout when the pin wiggled and had to be sent in for warranty. 

The cable looks and feels good…but falls short because of the memory wire. I’m guessing it’s useful if you’re actually using the U12t on-stage. But from a practical standpoint the stuff is a nightmare. It exacerbates the strain on the pin connector point, and makes it one hell of a hassle getting the U12t into its case. 

As for the case, I actually rather like it. Sure, it doesn’t look fancy, but I’ll take function over form any day. And unlike a lot of other cases, it’ll actually protect your IEMs and it holds all the accessories you could need for the U12t. 

Fit, Isolation, and Comfort

Now that I’ve finished making fun of the U12t’s janky packaging and accessories, it’s mostly uphill from here. Because frankly, it doesn’t matter how good the sound of an IEM is if you can’t wear it comfortably. 

To this effect, the U12t are the most comfortable IEMs I’ve used; I attribute this to a couple factors. First, the shell is nothing special. It’s of a standard size and doesn’t try to penetrate the confines of your ear like some other IEMs do. And second, 64audio’s Apex (air pressure exchange) technology really works. I don’t get that annoying build-up of pressure like I do with my other IEMs. In tandem, the simple shell ergonomics and Apex tech make the U12t something that I could listen to literally all day. 

As always, fit is 100% subjective. But definitely give these a shot if you can’t stand that ticking, time-bomb feeling of pressure building up in your eardrums. 

Sound Analysis

Testing Methodology:

• FLAC files off of a Shanling M0 with the stock cable and stock tips. 
• My genres of preference include country, film scores, instrumentals, EDM, and pop. 
• Burn-in – Don’t really believe in it, unless we’re talking about your brain and ears getting used to the sound. I am the second or third owner, so I’d imagine that they have well over a hundred hours on them at this point. 
• The U12t requires minimal power to drive. There’s no hissing with any of my sources. I also don’t listen any louder than 75dB, so all you head-bangers take that for what you will. 

Bass: BAs are known for their speed and detail, but they often lack the authority of a traditional DD. Luckily, this isn’t the case with the U12t: It has exceptional bass for a full-BA setup. As you might expect, it’s tight and controlled, and yet there’s no shortage of extension, rumble, or thump. Even with bass-heavy EDM songs, I struggle to find fault with the bass. So while the U12t’s bass might not be quite on the same playing field as some flagship DD IEMs – as it does have a little of that icky plastic texture – it’s no slouch. Swapping the M15 module for the M20 module will also give you a slight bass boost.

Mids: The U12t doesn’t play favorites here like some other IEMs. Both female and male vocals are smooth, have good body, and hang to the back a little. I certainly wouldn’t call them thin, but they’re also not fat thick. Vocals always come first for me, and I was instantly impressed with the U12t’s midrange. There’s a pleasant, slight haze to the midrange as a result of the tone. Sure, vocals and instruments don’t sound 100% accurate here, but what IEM ever will? 

Highs: The U12t makes use of the Tia (tubeless driver) for the highs. If I could sum up the treble response in a few words: Natural and detailed. It’s certainly not like some V-shaped signatures that boost the treble to give the appearance of detail. I’d imagine that for a lot of people this will be the U12t’s standout, but…I’m not much of a treble-head, so most of the time it just takes a backseat for me which is exactly where I want it. 

Overall, the U12t has a warmer, darker tone and a smooth, slick presentation. This presentation does come with some concessions in pure resolution; however, make no mistake that the tuning’s been well-done. It’s not quite a laid back sound, and yet I find that I can listen without fatigue for hours on end. I’ve even found myself almost fall asleep with these on numerous times, but in a good way: They just sound so good, I can’t bring myself to take ’em out.

Let’s talk about technicalities because the U12t plays ball here too. As I touched upon earlier, resolution does take a small hit, especially in the midrange. Despite this, the U12t is still incredibly resolving, and I think it would compete favorably with most other flagship stuff. Something special about the U12t is the timbre – it is extremely clean, more so than any other BA setup I’ve heard. Imaging and layering are also stellar as one might expect. The more recessed midrange creates a sense of depth I’ve rarely found with other IEMs, and as a result the U12t diffuses from the head-stage to a good extent.

The Verdict

When I first saw the U12t online, I balked at the price. Just the fact that such expensive IEMs existed blew my mind. But also, who in their right mind would spend $2000 on a pair of IEMs?  I think you can guess who (mostly) ate their own words and fell down the rabbit hole.

Let’s talk about value. This is where things get murky because I haven’t actually heard any other flagship IEMs yet. Devoid of this fact, do I think the U12t are worth $2000? Some people will hate me for saying this, but to be blunt – not really. I certainly wouldn’t pay that much (I paid closer to half), and I think even most audiophiles would struggle to justify the price. Of course, this sentiment is applicable to most audio gear in general, and the end rarely justifies the means. So the only time I think something like this can be truly called “worth it” is if it’s your endgame. 

This begs the question: Who is the U12t for? As someone once infamously said: The U12t is not special. It’s that kid in school that gets 90% on every subject, but can’t seem to get a perfect score in anything. If there’s a specific aspect of the frequency range or of technicalities you’re partial to, then there’s better options. The more I’ve listened to the U12t, the more I’ve realized that there’s no single standout for me. But this is also why the U12t is probably the safest flagship IEM you can buy; it simply plays well with everything. It’s an exercise in when the whole is greater than the sum of its parts, and most would agree that’s a sort of special in itself.

Score: 8.5/10 (Excellent)

Understanding my score: This is a personal, subjective assessment of an IEM’s sound quality. I don’t take into account any other factors. Take it with a grain of salt! I’m not going to lie; I have high standards. But I’m not telling anybody how they should hear something – it’s a reflection of what of me, myself, and I hear.