U18t
Eighteen Driver Universal In-Ear Monitor
Made in the USA
Packed with an unbelievable 18 balanced armature drivers per ear, the U18t is a groundbreaking personal listening experience.
This industry-first design pushes the limits of what an IEM can be, with a classic tuning refined to an extremely high level for those seeking maximal detail. Hear incredible texture and unmatched clarity across all frequencies, with a powerful low-end and mid bass.
Each ergonomic shell is machined out of a solid piece of aluminum and finished with an elegant copper-patinated inlay on the faceplates.
This is an IEM for anyone seeking to hear the utmost detail from their music. U18t is characterized by tight lows, super transparent mids, and a remarkable high frequency extension.
Its bass defies expectations of what balanced armatures can deliver, with a bodied mid-bass smoothly transitioning into the midrange, which has plenty of speed and range for vocals and instruments to shine with excellent instrument separation. Then, 64 Audio's signature tia treble provides unique air extension, sparkle, and detail.
The depth of U18t's soundstage is exceptionally large, with precise spatial imaging — tall and and deep, it's even great for movie watching or playing games.
U18t 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. U18t 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 U18t 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 U18t by default, offering full-bodied warmth 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 balanced bass extension, while allowing you to hear some more of your surroundings.
- The mX module (-10dB noise isolation) lowers the bass quantity, opening up the soundstage and reducing isolation even further for ambient awareness.
CABLE

U18t'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

- U18t 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
- m15 apex Modules
- mX apex Modules
- Round Sticker
Eighteen precision balanced armature drivers
Driver Configuration
1 tia high, 1 high-mid, 8 mid, 8 low
Sensitivity
111 dB/mW @ 1kHz
Impedance
9Ω @ 1kHz
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.