Like today's most advanced exotic supercars, the chassis and body must be extremely solid to extract maximum performance. The FH5's patented TRISHELL structural design ensures that this is the case, with a 5-axis CNC machined aluminum-magnesium alloy rear shell, body, and front covers fixed tightly together with multiple screws – greatly reducing excess resonance and distortion.

Pure, raw lows
The FH5's low frequency sound tube adopts FiiO's patented S.TURBO acoustic structural design. With its specially designed turbine-inspired design that makes clever use the physics of sound waves, you get meaty, deep bass that is more than capable of letting you feel the music. S.TURBO also filters out unnecessary mid and high frequencies produced by the bass driver ensuring a more seamless transition between the lows and highs. 

The FH5 allocates one sound tube each for the low, mid, and high frequencies. These tubes have been designed to impeccably integrate with the 4 driver units, allowing for a wonderfully smooth transition between the three main regions of sound frequencies to maximize the drivers' combined potential, bringing you a phenomenal symphony of music.

Balanced Armature 
The FH5 employs a hybrid driver design that combines the best of balanced armature and dynamic drivers for an absolutely addicting sound. Low frequencies are deftly handled by a 10mm polymer nanocomposite dynamic driver, providing bass extension and quality beyond what you think is normally possible. Mid frequencies are produced by the Knowles ED30262 balanced armature driver, while high and ultra-high frequencies are created by the Knowles 31082 (greatly improved over the 30017) – specifically tuned to squeeze every last bit of performance from them. These four drivers per ear combine to provide thunderous lows, lush vocals, and sweet highs.

Comfort
The shell of the FH5 is of aluminum alloy precisely machined with CNC technology, ensuring that it will continue to luster for years to come. The FH5's shell design is also reminiscent of custom in-ears, which not only provides an extremely comfortable fit but also shines as a stylish accessory to wear.

Included with the FH5 are 13 different pairs of ear tips: 3 different sets of small, medium, and large pairs of ear tips: 1 set for balanced sound (with 1 pair applied to the earphones in factory), another set for enhanced bass response, and 1 set for enhanced vocals.

Also included are 3 pairs of foam ear tips all in medium and 1 pair of bi-flange ear tips.
With the great variety of bundled ear tips, anybody can tailor the sound to what they want in absolute comfort.

Quality 
The FH5 has been certified by the Japan Audio Society to be "Hi-Res Audio" capable. This means that the FH5 is capable of a frequency response up to 40kHz, which can fully reproduce the audio and give you a natural and life-like listening experience that truly lets you listen to the music the way the artists wanted it to sound.