Astell&Kern, which makes premium high-resolution audio devices, and 64 Audio, which devises in-ear monitor technology, have announced their first collaborative creation: XIO.
XIO features an advanced hybrid system with 10 tuned drivers and a four-way passive crossover. The result, says the companies, is a “vivid sense of depth and a spacious, realistic soundstage.”
A direct-radiating high-frequency driver eliminates the traditional sound tube, minimizing distortion and enhancing delicate highs with airy, detailed resolution. Six mid and one upper-mid balanced armature drivers ensure smooth transitions and rich textures.
The True Isobaric Dual-Dynamic Bass structure synchronizes two dynamic drivers in an acoustically neutral coupling chamber, achieving bass with depth, density, and impactful presence.
The X10 features several patented technologies developed by 64 Audio. tia (Tubeless In-Ear Audio) is a patented IEM design that minimizes resonance and distortion, delivering clear and vivid sound. The tia system consists of the tia driver, single-bore design, and acoustic chamber. XIO adopts the tia driver and single-bore structure to capture the pure essence of sound.
Apex (Air Pressure Exchange) is a patented venting system that naturally releases pressure from the sealed ear canal while maintaining excellent noise isolation, says the company. This technology reduces listening fatigue during extended sessions and provides a much wider, more realistic soundstage. The m15 module, standard with XIO, is specially redesigned for XIO with DLC coating on 904L stainless steel, making it a unique apex solution exclusive to this model.
There’s also LID (Linear Impedance Design), a patented circuit that compensates for nonlinear resistance between drivers, ensuring consistent sound quality regardless of changes in the output impedance of the source device. This technology provides a stable sound signature and accurate frequency response at all times.
The XIO’s housing is crafted from precision-milled 904L stainless steel, a material notably tougher and more challenging to machine than conventional stainless steel. Its black DLC (Diamond-Like Carbon) coating delivers a premium texture. The faceplate, echoing Astell&Kern’s design heritage, shows a three-dimensional presence through intricate reflections and deep shading.
Completing the design is a dedicated silver-plated UP-OCC copper Litz cable, specially designed to harmonize aesthetically with XIO. The four-core cross-braided cable ensures excellent “noise shielding, transparent signal transmission, and with an ultra-low impedance of just 0.29O, maximizes electrical efficiency.”
Each unit uses carefully selected components sourced globally, then designed, assembled, and quality-checked by expert engineers in the U.S.
The XIO Universal in-ear monitors come with a 64 Audio premium leather case; TrueFidelity foam ear tips (S, M, L); SpinFit silicone ear tips (S, M, L); standard silicone ear tips (S, M, L); cleaning tool and cloth; cable clip; 4.4mm silver-plated UP-OCC copper Litz cable; and Apex Modules: m20 (Silver), Special m15 (904L Stainless Steel with DLC Coating), m12 (Gold), and mX (Black).
First teased in May 2025 at the High End Show Munich, the X10 will be available at authorized Astell&Kern dealers worldwide in August 2025 for US$3,000.