FiiO JadeAudio JT9

Open Back Planar Magnetic Headphones 

• 95 x 86 mm proprietary planar driver
• 1 μm ultra thin diaphragm
• Patented sapphire and aluminum dual coating technology
• Patented uniform magnetic field design
• 28 nm grade process technology
• High sensitivity of 95 dB/mW, easy to drive
• Lightweight, foldable design at 365 g
• Custom tuned cable for planar drivers
• Includes both 3.5 mm and 4.4 mm headphone cables
• Hi Res Audio certification 

Proprietary engineering with a deep commitment to sound quality

95 x 86 mm proprietary planar driver

The JT9 is built around a large 95 x 86 mm diaphragm, giving it a natural edge in soundstage, bass extension and dynamic range. It is powered by planar driver technology developed in house by FIIO's acoustic engineering team. Developed using the latest manufacturing techniques and continually refined through real world listening feedback from previous generation products, every aspect, from production processes to key acoustic parameters, has been carefully optimized to deliver an even higher level of performance.

The improved manufacturing process lowers the driver's resonant frequency, allowing for deeper bass, a fuller and warmer sound signature and greater overall refinement. Complementing the driver is a newly designed ear cup structure that reduces the in the head vocal effect and expands vertical soundstage, creating a more spacious, natural presentation that stays comfortable to enjoy for hours.

Joseph, Chief Engineer of FIIO's IEM R&D Center, explains: “One of the key advantages of a planar driver is its exceptionally light, ultra thin diaphragm. With virtually no inertial mass to overcome, it can respond quickly to even the finest details in an audio signal. With the JT9, our goal was to create a planar headphone that is easy to enjoy for hours, with a spacious and well organized soundstage. To achieve this, we drew inspiration from both the JT7 and the FT1 PRO, incorporating a secondary sapphire coating process. The result is extended frequency response at both ends of the spectrum, more effortless bass, clearer treble and improved reproduction of string instruments.”

Ultra light, ultra thin, ultra responsive

1 μm ultra thin diaphragm

The large diaphragm delivers excellent bass extension and dynamic range, while its ultra thin construction enables exceptionally fast driver response. Featuring a 1 μm ultra thin diaphragm, the JT9 embodies the defining qualities sought after in planar driver design, extremely light weight and exceptional thinness, allowing it to achieve remarkable performance within its class. Its exceptionally fast transient response lets it faithfully reproduce the finest musical details, from the delicate harmonics of a violin to the lingering shimmer of a triangle. With outstanding dynamic range and excellent frequency response, the JT9 captures every nuance with remarkable precision.

Two advanced materials, one synergistic design

Patented sapphire and aluminum dual coating technology

The JT9 is built around one of FIIO's signature acoustic patents, the dual coating technology, patent number ZL2024205488218. Starting with a high performance PET diaphragm substrate, natural sapphire and metallic aluminum were carefully selected for a precision dual layer coating, comprehensively optimizing frequency response across the entire range. The result is a dramatic leap in resolution, letting listeners experience the refined, nuanced sound quality and captivating tonal character unique to planar drivers.

Aluminum: lightweight aluminum improves voice coil conductivity, lowers impedance and makes the headphones easier to drive while delivering a wider dynamic range.

Sapphire: sapphire's exceptional hardness increases diaphragm rigidity, enhancing high frequency resolution and clarity while contributing to the headphones' distinctive tonal character.

Masterful craftsmanship, semiconductor grade precision

28 nm grade manufacturing process

The JT9 incorporates a 28 nm chip level fabrication process derived from semiconductor manufacturing. The conductive voice coil is processed in a 6.6 x 10⁻³ Pa high vacuum environment, completely isolated from air. The chamber is then heated to 120°C, transforming the required metal target material into ionized particles. Through electrostatic attraction, these ions are deposited evenly and securely onto the diaphragm surface, forming the precise coating thickness required by the acoustic design. This highly controlled manufacturing process delivers exceptional production precision while enhancing the durability and long term reliability of the conductive voice coil.

Balanced magnetic field for lower distortion

Patented uniform magnetic field design

Traditional rectangular magnet arrays often produce uneven magnetic field distribution, resulting in inconsistent force acting on different areas of the voice coil, which can induce diaphragm break up and increase distortion. To address this, the JT9 incorporates FIIO's proprietary uniform magnetic field technology, patent number ZL202420884963.1. By optimizing the magnetic circuit and using custom shaped high strength magnets, the JT9 creates an exceptionally uniform magnetic field across the entire driver. This allows the entire diaphragm to move with more consistent excursion and driving force, effectively suppressing diaphragm break up at its source. The result is significantly reduced distortion, with fine musical detail preserved with exceptional clarity.

Easy to drive, great sound anywhere

95 dB/mW high sensitivity for effortless driving

With a sensitivity of 95 dB/mW at 1 kHz, the JT9 requires significantly less driving power than conventional planar headphones. Whether connected to a smartphone with a portable DAC/amp dongle or other everyday source devices, the JT9 is easy to drive while delivering a rich, full bodied sound, so outstanding planar sound stays within reach wherever you listen.

Welcome to a lighter era for planar headphones

365 g lightweight, foldable design

The JT9 breaks free from the age old problem of heavy, uncomfortable planar headphones. Wear it for hours and barely notice it is there.

Just 365 g: about 40 g lighter than typical full size planar headphones, which usually weigh over 400 g and make head pressure and neck discomfort more likely during extended listening sessions. The JT9's lighter weight eases that burden so listeners can immerse themselves fully in music for hours on end.

Foldable design: the rotating, foldable ear cups collapse into a compact form that is easy to store and even easier to take along, whether at home or on the move.

3D ergonomic design: shaped to mirror the natural contours of the human face, its streamlined 3D design hugs the cheeks perfectly. Paired with a three axis rotation structure, it delivers a superior seal, a closer fit and even, balanced clamping force for all day comfort.

Ergonomic headband: the headband supports multi axis rotational adjustment, with the ear cups and connectors rotating and extending smoothly and freely. Whatever the head shape or ear contour, it offers a tailor made fit.

The right cable for the right driver

Custom tuned cable for planar drivers

A great driver deserves an equally great cable. That is why a specially tuned cable was developed around the acoustic characteristics of the JT9's planar driver. Made from high purity oxygen free copper, it combines 0.06 mm, 0.08 mm and 0.12 mm copper strands into a substantial 22 AWG conductor. Carefully tuned to complement the driver's performance, it enhances the weight and body of the mids and bass, delivers a more spacious and natural presentation and enhances bass impact and ambience, bringing every note to life with rich, effortless energy.

Ready for a wide variety of sources

Includes both 3.5 mm and 4.4 mm headphone cables

The JT9 includes a 3.5 mm to dual 3.5 mm single ended cable, a 4.4 mm to dual 3.5 mm balanced cable and a 6.35 mm to 3.5 mm adapter as standard. Whether connecting to different source devices or tailoring the setup to personal listening preferences, listeners can choose whichever cable best suits their needs, for more ways to experience the music.

Officially designed, thoughtfully complete

Water resistant storage case included

The JT9 comes with an official storage case, making storage and transport simple and worry free. Made from water resistant, moisture resistant woven fabric, the case is sized to fit the JT9 precisely, providing dependable protection wherever it goes.

Hi Res Audio certified

Industry recognized sound quality

An authoritative stamp of approval for exquisite planar sound. The JT9 has earned official Hi Res Audio certification from the prestigious Japan Audio Society (JAS). With benchmark setting audio performance, it masterfully recreates the purity, nuance and detail of a live musical performance.

Understated elegance

Two color options

Available in classic black and a retro deep brown. These refined tones add a premium touch to the JT9's sleek contours. Whichever color is chosen, the JT9 becomes a true audio artwork that expresses a personal style.

Note: the deep brown edition is expected to launch officially in September 2026. Stay tuned.