U12t
Twelve Driver Universal In-Ear Monitor
Made in the USA
64 Audio’s best-selling universal in-ear monitor features renowned resolution and a detail-oriented sound signature that delights even the most discerning listeners.
The U12t does it all, delivering immersive sound and impeccable spatial imaging. Its clean highs extend beautifully with a warm and engaging low-end response. Offering reference-level detail, this IEM is among the best for everyday music lovers, audiophiles, musicians, and sound engineers.
Each ergonomic shell is machined out of a solid piece of aluminum and finished with an elegant brushed aluminum faceplate.
If you've heard it, you probably understand — U12t has quickly become the "endgame" IEM for many, with its sound signature that plays well for nearly anything and anyone.
It starts with a speedy, textured, nuanced bass that delivers natural decay. The midrange is smooth and deep, allowing for vocals and instruments to feel as if they're unfolding right in front of you within the soundstage. And treble is ultra-detailed, with microdetails in the highest audible frequencies thanks to 64 Audio's patented tia driver.
The twelve drivers unite to create a sound signature that is far greater than the sum of its parts, with high detail retrieval, clean timbre, precise imaging, and surprising dynamic range between the loudest and and quietest parts of your favourite songs.
U12t features exclusive technologies that challenge traditional in-ear monitor designs to give you the absolute best listening experience.

Tubeless In-Ear Audio
64 Audio's tia is a patented IEM design methodology that aims to reduce unwanted resonance and distortion for a transparent and lifelike sound signature. U12t features two major elements of the tia system:
The tia driver is an open balanced armature speaker design that brings new meaning to resolution and transparency. It delivers airy, crisp, and microdetailed upper frequencies with characteristics not often found in a headphone or in-ear monitor. By opening a balanced armature, the diaphragm becomes fully unobstructed, unleashing the sound potential of the driver. This eliminates a lot of the vibrations and resonances that are inherent in conventional, closed balanced armature designs. With this new method of producing and delivering sound to the ear, conventional sound tubes and dampers are no longer necessary.

The tia single-bore design is a huge leap forward in eliminating unwanted tube resonance. The large bore itself serves as a sound-shaping chamber and aids the tia high driver in delivering a linear and coherent frequency response. Because of the extremely short sound path of the tia high driver, a remarkable high-frequency extension and smoothness is achieved. The large single bore also helps prevent clogging of the tip and obstruction of sound.

Air Pressure Exchange
Apex is a patented vent that releases air pressure in a sealed ear canal all while retaining a level of isolation; this venting alleviates listener fatigue and allows for a much more realistic soundstage.
When you seal a miniature speaker in an ear canal, the air inside becomes trapped. As the speaker produces sound, it moves the air and causes the eardrum to work excessively. The pneumatic pressure exerted on the eardrum causes ear fatigue. Apex relieves this pressure, allowing the eardrum to move naturally, so you can comfortably listen longer.
Apex enables air to move freely in the ear canal, which extends the perceived soundstage and allows for a more natural listening experience. Everything from inserting, wearing, and removing the IEMs becomes a much more natural and painless process.
Apex is implemented in U12t via interchangeable modules, so you can quickly switch between different levels of isolation and sound signatures. Although the modules technically only affect the low frequencies, this psychoacoustically affects your perception of the whole frequency range.
- The m20 module (-20dB noise isolation) is fitted to U12T by default, offering a pronounced sub-bass shelf with the type of isolation you'd expect from a conventional IEM, minus the ear fatigue.
- The m15 module (-15dB noise isolation) is a popular choice for maintaining a smooth and warm sound, while allowing you to hear some more of your surroundings.
- The mX module (-10dB noise isolation) lowers the bass quantity for a more typical "neutral" listen, opening up the soundstage and reducing isolation even further.

Linear Impedance Design
Smartphones, body packs, amps, and DAPs produce audio with different output impedances. The interaction of the earphone impedance curve with the sources may result in the same IEM sounding different with different sources.
LID is a proprietary circuit that corrects the non-linear impedances of the multiple driver-sets that comprise this twelve-driver IEM, restoring proper interaction with the source and preserving the desired sound signature, so you can enjoy the same sound reliably across sources.
CABLE

U12t's packaging and accessories have been updated, and now includes a new, low resistance cable in black.
It features a branded straight 3.5mm metal jack, as well as a metal synch and branded metal bifurcation.
Our classic angled 2-Pin connectors are situated at the end of an ergonomic curve in the cable to accommodate a comfortable fit around the ear without a memory wire. The new soft jacketing minimizes tangling and microphonic noise.
- .78mm Pins
- 0.23 Ohms Total Impedance
- 7 x 7 x 4 Multi-Twist
- Silver Plated OCC Copper Wire
- 26 Awg
IN THE BOX
- U12t Universal In-Ear Monitors
- 64 Audio Premium Leather Case
- TrueFidelity Eartips (S,M,L)
- Silicone Eartips (S,M,L)
- SpinFit Eartips (S,M,L)
- 48" Black Premium Cable
- m20 apex Modules
- mX apex Modules
- m15 apex Modules
- Round Sticker
SPECIFICATIONS

Driver Type/Count
Twelve precision balanced armature drivers
Driver Configuration
1 tia high, 1 high-mid, 6 mid, 4 low
Sensitivity
108 dB/mW
Impedance
12.6 +1/-2 Ω from 10Hz – 20kHz
Crossover
Integrated 4-way passive crossover
Isolation
-20dB with m20 apex module (default)
-15dB with m15 apex module
-10dB with mX apex module
For hygienic reasons, there are no returns on earphones once opened.
All our earphones are available for personal demonstration in-store. We encourage you to try before buying to ensure satisfactory sound, fit, and functionality.
If an item is defective upon receipt, please notify us within 30 days of purchase so we can arrange an exchange. For issues following 30 days, we will work with you and the manufacturer within the scope of each brand’s warranty and service policies.