64 Audio is the world's fastest-growing custom in-ear monitor (IEM) company, founded in July 2010 by Vitaliy Belonozhko and his wife Anastasia in Portland, Oregon, originally under the name '1964 Ears' before rebranding to 64 Audio in September 2010. The company was born from Vitaliy's desire to create better and more affordable in-ear monitoring solutions, starting with building a single set of IEMs for his wife Anastasia around 2008. Vitaliy Belonozhko, a Ukrainian immigrant who came to the United States at age 10 in 1992, is a sound engineer with over a decade of experience working with musicians and production companies in the Northwest. Now based in Vancouver, Washington, 64 Audio employs the four Belonozhko brothers (Vitaliy, Roman, Vlad, and Bogdan), all musicians and sound engineers with backgrounds in professional live music production and stage performing. The company has revolutionized the IEM industry through patented technologies including APEX (Air Pressure Exchange) pneumatic vents that release ear canal pressure and reduce listener fatigue, 3D-Fit technology combining digital scanning and 3D-printing for precise custom fits, and TIA technology that delivers sound directly without internal tubes. Since 2010, 64 Audio has handcrafted thousands of custom in-ear monitors for world-class musical talent, with all custom and universal IEMs designed, assembled, and quality-controlled by highly skilled technicians in their U.S. facility, offering award-winning products like the A12t and A18s that serve as the gold standard for performing artists across genres while maintaining a 30-day fit guarantee for customers worldwide.
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The Astell&Kern XIO is a premium wired IEM with 10 drivers, released in collaboration with 64 Audio.
The housing is crafted from durable Stainless Steel 904L with a DLC coating, ensuring a premium finish.
It features a four-way crossover and proprietary technologies like LID and tia for precise sound reproduction.

64 Audio celebrates its 15th anniversary, originating from a family project in Portland and evolving into a global IEM leader.
The company introduced innovative proprietary technologies including apex® for pressure relief, tia™ for direct driver sound, and 3D‑Fit™ for customized comfort.
Iconic IEM models like U12t and A18s are trusted by audiophiles and artists, including notable users like Beyoncé and John Mayer.

The XIO IEMs feature 10 drivers, including dual dynamic and balanced armature drivers, for full-spectrum audio (5Hz-22kHz). * The 904L stainless steel housings with diamond-like carbon coatings ensure durability and a premium aesthetic. * 64 Audio's innovations, like tubeless audio and air pressure exchange, optimize sound quality and wearing comfort. * The included silver-plated UP-OCC copper Litz cable enhances signal purity and reduces interference. * Retailing for $3,000, the XIO IEMs represent a premium choice for audiophiles, launching August 2025 in the U.S.

The Astell&Kern and 64 Audio collaboration introduces the XIO In-Ear Monitors, priced at $3,000, targeting audiophiles with premium sound quality.
Featuring a ten-driver hybrid setup with 4-way passive crossover, it delivers precise frequency alignment and superior sound reproduction.
Incorporates 64 Audio's patented technologies like apex® and LID® for enhanced comfort, noise isolation, and consistent sound quality across devices.
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