Astell & Kern Stella Volk Audio X IEM Earphones

Experience the fruits of precision-engineered audio with theAstell & Kern Stella, a pair of professional IEMs co-designed by Volk Audio for cutting-edge audio reproduction. Sporting an innovative 12-driver dynamic/planar/balanced armature/electrostatic system with a six-way crossover, these IEMs expertly manage phase, pressure, and motion for a completely natural sound.

Five precision sound tubes with specially engineered vents control airflow for optimized audio reproduction. The build quality of the IEMs is extremely robust, with the titanium shells sporting a black anodized finish, sapphire crystal glass faceplates, aluminum central plates, and stainless-steel faceplate frames. The detachable 4.4mm TRRRS balanced audio cable sports a hybrid 5N LCOFC, 4N silver, and 12k gold internal conductor design that ensures ideal signal integrity and linearity. The Stella IEMs include the detachable cable, three pairs of silicone eartips, three pairs of foam eartips, an IEM pouch, a cable holder, and a leather carrying case.

Stella is the result of three disciplines guided by a single pursuit of truth in sound. Astell & Kern represents the precision of modern engineering. VOLK Audio defines the architecture of design and acoustic form. Michael Graves brings the mastery of a five-time Grammy Award-winning engineer who understands the line between control and emotion. Led by VOLK founder Jack Vang, whose decade of experience helped shape a generation of in-ear design, the project evolved through exchange and refinement.

Each discipline strengthened the others, creating an instrument defined by proportion, balance, and restraint. Throughout development, the VOLK engineering team worked closely with Astell & Kern to advance both process and performance. New acoustic architectures and driver assemblies were created specifically for Stella to achieve the precision and tonal balance defined in its target response. These innovations were refined and calibrated through extensive sessions with Michael Graves at Osiris Studio in Los Angeles. Each evaluation focused on tonal accuracy, phase alignment, and spatial coherence, ensuring that every decision served the music itself.

Stella is built on a 12-driver quadbrid architecture that unites four transducer technologies within a single, coherent system. Each element was developed for its distinct role and tuned through precise control of phase, pressure, and motion. Its design reflects the same discipline that governs its form.

Every contour, cavity, and circuit exists to serve acoustic integrity. The structure is shaped by performance, the performance defined by structure. Nothing is decorative, nothing is redundant. Every driver operates within its natural range, contributing its character without interference. No forced equalization. No artificial enhancement. Only precision through purpose.

• The LF-H system uses Volk M9-R 9mm subwoofer with dual-Sonion armatures
• Tri-armature midrange
• The HF-H system uses Volk MP-2 dual planars with quad Sonion electrostatic tweeters
• 6-way crossover network with multi-stage internal damping and tuned chassis venting

The VOLK Low-Frequency Hybrid System (LF-H) serves as the starting point of Stella’s multi-stage architecture, combining VOLK’s M9-R 9mm subwoofer and dual-balanced armatures within a dual-stage chamber designed to regulate phase and resonance.

The chamber’s geometry, alignment, and crossover were co-developed to maintain phase accuracy and pressure balance between both stages. This coordination allows the dynamic driver to deliver depth and force while the armatures add speed, texture, and tonal structure across the lower band. Operating from 20 to 600 Hz, the LF-H establishes a foundation of weight and control that defines Stella’s composure and balance.

Stella’s midrange is formed around a tri-armature array tuned for tonal balance and natural presence. The dual balanced-armature drivers operate from 600 Hz to 7 kHz, voiced for energy and density in the 1 to 5 kHz range. They deliver warmth, articulation, and a vocal character that connects the low and high ranges with quiet precision.

Above them, a single armature extends from 6 to 15 kHz, overlapping to reinforce upper-mid harmonics and refine vocal and instrumental overtones. Its lightweight diaphragm and quick transient response preserve clarity and texture while integrating precisely with the planar and electrostatic systems above, maintaining linearity across the spectrum.

The VOLK High-Frequency Hybrid System (HF-H) defines the upper range of Stella's architecture, combining VOLK’s MP-2 dual-planar magnetic drivers with four electrostatic tweeters in a unified system. The crossover and acoustic topology were co-engineered to preserve phase accuracy and tonal stability across the transition between the planar and electrostatic assemblies.

This balance allows the planars to shape upper harmonics with precision and control while the electrostatics extend bandwidth and atmosphere with speed and composure. Operating from 9 to 45 kHz, the HF-H maintains coherence and clarity at the limits of extension, completing Stella’s spectrum with authority and refinement.

• Shell: machined from aerospace-grade 6061-T6 aluminum and anodized in satin black, the shell forms the structural core of Stella. It holds every acoustic element in precise alignment, maintaining stability between the driver assemblies and the enclosure. Its geometry is engineered for stiffness and resonance control. Internal mass and surface continuity stabilize the structure, reducing vibration and preserving acoustic accuracy. The alloy’s low density provides comfort while preserving strength and balance.
• Central Plate: machined from 6061-T6 aluminum and finished in satin black, the central plate forms the visual and structural centerpiece of Stella. Positioned between the shell and the frame, it maintains geometric balance across the assembly. The VOLK and Astell & Kern insignias rest in opposition, each centered within its own field. The constellations surrounding them trace independent paths yet follow the same proportion and order. It is both ornament and structure—the expression of balance and craftsmanship that defines Stella.
• Sapphire Crystal Glass: cut from a single block of optical-grade 9H sapphire crystal glass, the panel completes Stella’s faceplate assembly, uniting the stainless-steel frame and central plate into a single, sealed structure. The surface is then diamond-polished to eliminate micro-distortion, achieving complete transparency and visual purity. The result is a structural lens of pure sapphire, engineered for rigidity, precision, and continuity of formimg
• Faceplate Frame: the frame defines the structural boundary between the sapphire glass and the aluminum chassis, machined to micron precision from stainless steel. Each surface is polished to a mirror finish, reflecting the precision of its form and the materials it unites. Beyond structure, it regulates the interface between air and material. The venting architecture built into the frame equalizes internal pressure and suppresses resonance, maintaining balance across the entire acoustic system. Every edge, radius, and transition was modeled to direct light and form as one continuous surface.

Machined into the aluminum shell and stainless-steel frame, the vent system regulates airflow throughout the enclosure. Its geometry equalizes internal pressure, stabilizing diaphragm motion and maintaining linear driver response. Each aperture is defined by depth, diameter, and damping profile to balance pressure relief and isolation.

This prevents standing waves and suppresses low-frequency bloom while preserving the integrity of the acoustic chamber. The vents function as a unified pressure-control system, ensuring consistency between both channels and completing Stella’s structural and acoustic equilibrium.

Stella features a proprietary six