Astell&Kern, the global leader in premium portable high-resolution audio devices, introduces its latest in-ear monitor (IEM), the AK ZERO1, featuring three different types of drivers to deliver a ground-breaking hybrid sound. Composed of a micro planar dynamic driver, dual balanced armature (BA) drivers and a dynamic driver, this unique design combines the sonic characteristics of each driver to produce an unprecedented natural audio. Astell&Kern has set new standards in IEM engineering to get the music fan closer to the original studio sound.
Astell&Kern AK ZERO1 features and innovations include:
- Three different types of drivers: Planar, balance armature and dynamic
- Perfectly harmonised driver structure
- Precision crossover network design
- Acoustic chamber created using 3D printed technology
- Precise CNC-machined metal housing
- Hi-fi-grade pure silver-coated OFC cable for improved transparency of the audio signal
Micro planar dynamic driver
The Micro Rectangular Planar Dynamic Driver is a specially developed, highly advanced driver that allows a planar driver design, normally difficult to scale down for headphones, to be applied to in-ear monitors. Adopting a sturdy and lightweight planar membrane to minimise frequency loss, this is combined with a vibration panel boasting a high-polymer and thin metal film to create crystal clear and dynamic high frequencies.

Dual balanced armature and dynamic drivers
The AK ZERO1’s driver system also features dual BA drivers, using custom-designed coils to deliver transparent vocals with super-low distortion. Couple this with the single 5.6 mm dynamic driver to ensure rich, controlled and deep low frequencies and the AK ZERO1 is poised to deliver its pioneering hybrid sound.
Crossover design
To realise this new sound through the ideal frequency response, a Crossover Network design was generated based on a thorough understanding of each driver’s parameters. Once established, each driver is carefully placed in the optimal position, enclosed in specifically designed acoustic chambers manufactured with 3D printing technology. These precision enclosures cleverly eliminate unnecessary movement and resonance from the drivers to ensure a stable performance. Lastly, the main precision-tooled housing reduces internal and external vibrations to deliver the most focused and accurate sound possible.
Hi-fi grade pure silver-coated cables
To further maximise the audio performance the AK ZERO1 arrives equipped with a pure silver-coated OFC cables. Exquisitely crafted with high-purity silver plating and copper, alongside aluminum plugs, this design strives to maintain transparency of the audio signal. Elsewhere, the MMCX connectors ensure a prime-quality connection between the ear housing and cable, offering a long-lasting and stable performance.

NEW 4.4mm MMCX Cable accessory
For discerning audiophiles looking to experience the highest quality audio possible from their AK ZERO1 IEMs or any other MMCX-connector compatible headphones, Astell&Kern is launching an optional 4.4mm cable. The PEP11 sports larger aluminium-machined 4.4mm plugs and features the same top-quality high-purity silver plating and copper cable.
Signature Astell&Kern design
Astell&Kern’s recognisable bold diagonal design language continues on the AK ZERO1, with the premium cut metal surface brilliantly reflecting the light. The shape of the housing and the slender ear nozzles have been carefully designed and refined to not only provide a secure and comfortable fit, but to deliver the sound efficiently and accurately through your ears. To further provide a snug fit, five different-sized pairs of silicone ear tip and one set of foam tips are supplied, along with a carry case to keep your IEMs pristine during transit.
The Astell&Kern AK ZERO1 is priced £649 / $699 / €749 and is available now from www.astellkern.co.uk and local independent dealers.
The Astell&Kern PEP11 is priced £119 / $130 / €139 and is available from www.astellkern.co.uk and local independent dealers.
Technical specifications
AK ZERO1
Drivers: Hybrid Drivers
- Special Micro Rectangular Planar Dynamic Driver x1
- Custom Balanced Armature Driver x2
- 5.6mm Micro Dynamic Driver x1
Connector type: MMCX
Housing material: Aluminum
Frequency Response: 25Hz–30KHz*
SPL: 96dB@1KHz (1mW)*
Impedance: 16Ω@1KHz*
Total Harmonic Distortion: 0.7%@1KHz
PEP11
Connector type: MMCX
Cable core: 4
Cable material: Silver, Copper
Plug: 4.4mm
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