64 Audio’s latest UIEM, Duo, is a dual driver hybrid design. Built with the complete Tia System, Apex Core, Wave Sync, and LID, Duo presents 64 Audio’s signature balanced sound in a whole new way. The simple audio design captures the listener’s auditory senses while forgetting they’re wearing IEMs in the first place.

The complex faceplate assembly not only serves an important role in protecting the shell of the IEM while allowing air to flow freely, it is also a major step in 64 Audio’s product design evolution. Duo is a timeless and elegant design reminiscent of open-back over-ear headphones.

SOUND

Duo feels light, leaving your ears feeling open and relaxed even for long listening periods. You feel simultaneously connected to your physical surroundings while you’re enveloped by music. Relaxed tonality lets you put them on and get lost. It’s able to present a non-analytical top-end while retaining air and sizzle. The vast open air sensation supports an unobstructed soundstage with impactful center imaging (unlike many other open back headphones) as well as no loss of bass. Duo effortlessly produces deep and rich low frequencies with plenty of sub bass.

TECHNOLOGY

Exclusive technologies that challenge traditional in-ear monitor designs to give you the absolute best listening experience

Duo features the following unique technology:

Tia

Rather than constricting the sound of the drivers by fitting a tube onto them, Duo’s complete Tia System reduces unwanted resonance and distortion by allowing the 9mm Dynamic Driver + Tia High Driver to radiate freely into the single large Tia bore with no obstructions to the front of the drivers.

Apex Core

Apex Core is a deeper understanding of air movement within an earphone system. Duo’s faceplate features a striking perforated grill that leaves the shell of the IEM open to the outside atmosphere for a less obstructed airflow resulting in an effortless reproduction of music and minimal physical fatigue.

Wave Sync

Due to the high crossover point between the two drivers, Wave Sync was developed to ensure coherence; another industry first. By using a type of “all-pass” filter, we’re able to introduce a crossover while correcting for time without having to change the physical distance between the drivers.

SPECIFICATIONS

Driver Type/Count	2 Drivers - One dynamic driver and one balanced armature driver
Driver Configuration	1 tia high, 1 dynamic low
Frequency Response	20 Hz – 20 kHz
Sensitivity	98 dB/mW (98 dB @ 1 kHz @ 1 mW (95 mV)
Impedance	9 Ω
Crossover	Integrated 2-way passive crossover
Isolation	-12 dB internal apex technology

New Premium Cable

0.23 Ohms Total Impedance
7 x 7 x 4 Multi-Twist
Silver Plated OCC Copper Wire
26 Awg

IN THE BOX

Duo Universal In-Ear Monitors
64 Audio Premium Leather Case
TrueFidelity Foam Eartips (S,M,L)
SpinFit Silicone Eartips (S,M,L)
Silicone Eartips (S,M,L)
Black Premium Cable
Round Sticker

64 Audio Duo Dual Driver Open-Back Universal In-Ear Monitor