Duo is a two driver hybrid universal in-ear monitor (UIEM). Following Trió and Fourté, Duo is another fully tubeless design in our product range, with the added benefit of being one of the worlds only semi-open back UIEMs. Built with the complete Tia System, Apex Core, Wave Sync, and LID, Duo presents 64 Audios signature balanced sound in a whole new way. The simple audio design captures the listeners auditory senses while forgetting theyre wearing IEMs in the first place.

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 youre enveloped by music. Relaxed tonality lets you put them on and get lost. Its 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.

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 Audios product design evolution. Duo is a timeless and elegant design reminiscent of open-back over-ear headphones.

Technology

Apex Core
Apex Core is a deeper understanding of air movement within an earphone system. Duos 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.

TIA
Tubeless In-Ear Audio (tia) is a patented IEM design methodology that aims to reduce unwanted resonance and distortion for a transparent and lifelike sound signature. The tia system is comprised of three major elements: open balanced armature tia drivers, the tia single-bore design, and tia acoustic chambers. A12t features two major elements of the tia system: the tia driver and the tia single-bore design.

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, were able to introduce a crossover while correcting for time without having to change the physical distance between the drivers.

Technical Specifications