Supercharged Bass
With Patented S.Turbo design 

The bass frequency sound tube features FiiO's patented S.Turbo acoustic technology, which cleverly guides sound waves through a turbine shaped tube to enhance bass frequencies. As a result, while the bass is deep and powerful without being bloated and muddy. At the same time, this design also filters redundant frequency sound from the other higher-frequency drivers, ensuring a smoother connection between the bass and mids. In a nutshell, S.Turbo will give you a supercharged listening experience you won't forget.  

* Patent number: ZL2018211416279

Fatigue-free listening, semi-open acoustic design

The FH9 features a semi-open acoustic design incorporating FiiO's system of balanced pressure relief between the front and rear cavities. The result is more natural sound, and more comfortable listening in longer sessions due to greatly minimized pressure on your eardrums when listening.

Undesirable sibilance is often the result of driver units being placed into a shell with no consideration of how they interact with each other, making it more likely that unwanted resonances occur. Thus, using finite element analysis, FiiO specifically designed the FH9's shell to feature a notch filter which effectively eliminates unwanted resonances generated in the shell, sound tube, and cavity. The result is greatly minimized undesirable sibilance for a purer and more transparent sound. 

Ultimate purity
With unique notch filter 

The FH9 is FiiO’s first hybrid IEM to feature a self-developed 2nd generation DLC (diamond-like carbon) bass driver. Compared to the 1st generation driver, the magnetic circuit structure has been redesigned resulting in 20% higher magnetic density to better push the massive 13.6mm DLC diaphragm – which means an even more dynamic sound. And thanks to DLC’s outstanding rigidity and high damping coefficient, the FH9’s bass driver is capable of providing extremely quick transient response with extremely minimal distortion.

2nd generation FiiO DLC diaphragm dynamic bass driver

"The advantage of multi-unit products is that they can extract the advantages of different units and combine them. FH9 not only uses large-size moving coil units, but also uses Lou's ultra-high frequency moving iron units. The frequency response coverage is very wide and the energy density is large. This is very important for the playback of small energy information; for example, the ultra-high frequency energy is small, but it is extremely important, there is no sense of space, so better resolution requires sufficient sound density. If the density is enough to hear the string, it will feel sticky, the wind will be thick and full, and the percussion instrument will feel air vibration when it is knocked. The instrument and the human voice will sound more stable, more solid, and more like real sounds."

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Chief Engineer of FiiO IEMs R&D Center

The flagship FH9 comes standard with three interchangeable sound filters. Each sound filter has its own damping and filter density, allowing you to choose between three different sound signatures

Specially-tuned sound

interchangeable sound filters

Parameters

The beautiful stainless steel angled MMCX connectors are designed to make your wearing experience as painless as possible. Details such as the special angle allow you to more easily connect your IEMs for more comfortable wearing as well as the left blue right red indicators to quickly get you going. All serve to let you purely focus on enjoying your music.

Enhanced ergonomics,

stainless steel angled MMCX connectors

Materials with weak rigidity are slower to respond to voice coil movements and produce irregular ripple-like movements, causing distortion.

Because of its use of rigid DLC material, the diaphragm is more responsive to voice coil movements for less distortion and more accurate reproduction of sound.

Common diaphragm

Beryllium-coated DLC diaphragm

Diaphragm Movement Comparison Graps

Included with the FH9 is a high-purity pure silver cable with 8 branches of 28 wires each, for a total of 224 wires. Each wire is individually isolated and all are braided together in the Litz style. The outer sheath of the cable is made from environmentally friendly TPU, which not only sports a radiant transparent look but is also resistant against yellowing under long-term use and stiffening when in low-temperature environments.

Pristinely pure, high-quality high-purity pure silver cable

*Interchangeable audio jack is officially licensed from the patent by FABRILOUS.

HB5 carrying case*1, Bass ear tips*3 pairs (SML), Balanced ear tips*3 pairs (SML), Vocals ear tips*3 pairs (SML), Foam ear tips*2 pairs (M), Double-flange ear tips*2 (M), SpinFit ear tips*3 pairs (SML), Cleaning brush*1, MMCX removal tool*1, Magnetic clamp*1, Green/Black/Red audio filters*1 set, 2.5/3.5/4.4mm interchangeable audio plug*1 set, 8 strands of 224 wires each high-purity monocrystalline pure silver cable*1

*1 pair of SpinFit ear tips and 1 set of black filters are pre-installed at the factory

Wealth of accessories

Hi-Res Audio certified

"The advantage of multi-unit products is that they can extract the advantages of different units and combine them. FH9 not only uses large-size moving coil units, but also uses Lou's ultra-high frequency moving iron units. The frequency response coverage is very wide and the energy density is large. This is very important for the playback of small energy information; for example, the ultra-high frequency energy is small, but it is extremely important, there is no sense of space, so better resolution requires sufficient sound density. If the density is enough to hear the string, it will feel sticky, the wind will be thick and full, and the percussion instrument will feel air vibration when it is knocked. The instrument and the human voice will sound more stable, more solid, and more like real sounds."

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Chief Engineer of FiiO IEMs R&D Center

Fine-tuned curve, outstanding frequency response through meticulous engineering