Dynamic IEMs 

13.8mm large dynamic driver | Magnalium diaphragm DLC gasket driver W-shaped gasket | 1.5T magnetic flux | Frontal acoustic prism “Tesla Valve” bass  enhancement  acoustic  design  |  316L  stainless  steel shell Furukawa monocrystalline silver + Furukawa monocrystalline silver-plated copper braided headphone cable | Two colors available | Hi-Res Audio Certified

*Pictures are for reference only, actual product may vary.

Other diaphragms

A different kind of “big”


Effective diaphragm area increased by

The FD15 explores higher levels of core audio performance by increasing the diameter of the dynamic driver to an astonishing 13.8mm. Compared to its predecessor, the FD5, this results in an increase in effective diaphragm area of approximately 40%. Moreover, the larger the dynamic driver, the more air it can push through, thereby improving the efficiency of electroacoustic conversion at its source. This enhancement elevates the overall quality and scale, allowing mid-frequency vocals to feel as if they are right next to the ear.

Mid-range vocals,

Simply purely good

Quality materials yield quality sound, and HiFi is no exception to this principle. The FD15 features a thoroughly refined mid-range, with  genuine  innovation  in  the  usage  of  materials  and  new technologies. Once again, we strive to  adhere to the philosophy of simply providing great, pure sound.

13.8mm large dynamic driver

Within the FD15 is a frontal acoustic prism, which not only retains the widely  acclaimed vocals from the  FD5 but also  helps to  adaptively adjust  the all-new  driver and  enhances high-frequency  diffusion. Specifically,  engineers have  added a  specially  designed acoustic filtering  device at the front of the driver. When  sound  waves  pass through, this acoustic device effectively addresses the subtle sound delay  caused by  different  sound wave  paths,  achieving adaptive phase consistency and thus precise control over sound waves.

Greatly detailed for a truly high-end listening experience, frontal acoustic prism

All-around excellence, with professional attention paid to every aspect. Besides  just  achieving  high-quality  sound, we  place great  emphasis on  long-term  user  comfort. We  continuously improve and optimize the ergonomic design of our headphones to create an enjoyable and enduring high-end HiFi experience:

High-level comfort,

thanks to 6.7° Optimized for comfort

Carefully adjusted sound nozzle

Based on  user  feedback  and  multiple  optimized solutions, engineers have precisely adjusted theangle between the  sound nozzle and the  wearing  surfacea long the  Y-axis, raising  it  by  6.7°  while maintaining the length of the nozzle. This allows the earphones to better  fit into  the ear  canal, significantly  enhancing  both wearing comfort and stability.

Curved MMCX connectors

The typical rigid  right-angled  cylindrical MMCX shape has been transformed into a more ergonomic  curved shape that better accommodates a wider range of ear sizes. When worn around the ear, this design eliminates the discomfort caused by the earphone pressing against the back of the ear – another example of professional attention to details.


Optimized frontal contact surface

Through precise measurements and optimization, with the FD15 we have narrowed the contact area between the front of the IEM and the ear. This ensures a better fit, reduces  movement  caused  by  gaps and  minimizes friction - resulting in even more comfortable wearing. Just  one  more  example of our attention to even  the smallest  of details.

Specially optimized,with an emphasis on vocals Conversation with an FD15 engineer

“The FD15, in my opinion, is one of FIIO’s most balanced in-ear monitors, vocals-wise. But why do I say that? Because it produces a dense, perfectly lush  vocal  performance. It   magnetically  captures  the  voices  of  both  mid-range  and  low-frequency  singers,  truly  conveying the   emotions within  the voices  without  sacrificing  resolution. With i ts large  dynamic driver unit and  structural  design, the  FD15  delivers  deep and cohesive bass – making instruments like drum sound  solid  and  powerful. While it may not be the last word in detail in ultra-high frequencies like the very  best  multi-driver balanced  armature  earphones,  but in  dynamic and complex musical  passages  the  treble  remains  perfectly clear. The FD15 is also a  good  example of  exhibiting the qualities  expected  from a magnesium-aluminum driver, with a  large  soundstage. In s ummary, if I had  to  choose one  word  to  describe the FD15, it  would  be “grand”: grand sense of solidness, grand dynamics, and a grand soundstage.”

“Robust materials” for a robust sound

Magnalium diaphragm DLC gasket driver

With the FD15, we are sincerely bringing you into a new realm of sound. The all-new FIIO FD15, as the successor to the FIIO FD5,introduces a truly high-end driver design——a magnalium diaphragm DLC gasket driver. By  innovatively combining these two materials, not only does the FD15 deliver a spacious and relaxed natural  sound, but it does so while achieving new heights in the reproduction of musical detail for truly transparent sound.




Magnalium diaphragm——a scientifically calculated blend of magnesium and aluminum that features high hardness and low distortion when moved for clear, detailed treble.



DLC gasket——DLC diamond-like carbon is known for being both rigid yet flexible, which means less breakup during movement and ultimately higher-quality sound.

FIIO’s pursuit of acoustic excellence knows no bounds. The FD15 boldly embraces high-end audio design principles by introducing  the  W-shaped  gasket  design to  earphones. Compared to conventional diaphragms of the same size, the FD15 boasts a 30% increase in effective vibrating area. With a larger  effective  diaphragm area and  greater  amplitude, the core acoustic unit can store more  sound  energy, delivering a denser and more solid listening experience.

Reinventing sound with FD15

W-shaped gasket


*increase in effective vibrating area

A “sound” entry into excellence

Φ8.6mm long voice coil 

Based  on  perfessional design  principles,  the  voice  coil  diameter of the FD15 has been increased from the FD5’s Φ6.2mm to Φ8.6mm. The longer voice coil copper wire  directly  enhances  efficiency  and power  capacity,  resulting  in  improved  transients. The   result  is  a cleaner, more natural sound that fully allows you to fully appreciate its charming mids.


Voice coil 1.38 times of the FD5’s


Resulting in a 78% increase in driver power

Reliable enough

1.5T external  magnet design

The driver structure is of course one of the most important  parts  of  a   dynamic  driver  earphone.   The  FD15  draws inspiration  from innovative acoustic  concepts and adopts a powerful  external  magnet design. The  magnet  volume has increased by  about 69.5%, and the magnetic flux density  can reach up to 1.5T. This abundant and uniform energy supply ensures that this high-end driver consistently works well.


Magnet volume increased by


Magnetic flux density achieves up to

“Tesla Valve”  bass enhancement acoustic design

Inspiring new acoustic thinking, with special attention to  immersive bass. The FIIO FD15 takes the lead by incorporating the F.T.B.S. ‘Tesla Valve’bass enhancement acoustic design. Thanks  to  the high-precision powder metallurgy process used in creating the FD15, the  length, angle,  and  quantity  of  channels  within the  earphone cavity are specially calculated to achieve a Tesla valve fluid structure that significantly enhances bass extension. Experience truly deep yet detailed bass.

Deeper bass, for an emotionally deeper experience

High-end quality, without the high-end price 316L stainless steel shell

Silver light  flashes by, swift  as  a  shooting star. The  FIIO  FD15 creatively combines a fresh design language with a closed-back acoustic  design, utilizing  carefully  placed  design  surfaces flourishes to create an elegant and ever-changing play of light and shadow. To achieve this effect, the FD15 is made with 316L medical-grade stainless steel, which thanks to powder metallurgy sintering means the IEM is durable. It further undergoes meticulous hand-polishing and PVD electroplating for a premium finish, for a mirror-like visual sensation. Let its texture emotionally resonate with you.

Parts list


②--------------------------------------- Earphone cable*1

③------Balanced eartips S/M/L*3 pairs (M pre-installed)

④-----------------------------Vocal eartips S/M/L*3 pairs

⑤- -----------------------------Bass eartips S/M/L*3 pairs

⑥ --------------------------------- Foam earips M*2 pairs

⑦-----------------------------HS18 eartips S/M/L*3 pairs

-----------------------------------Storage case HB11*1

⑨---------------------------- MMCX quick release tool*1

⑩ -------------------------------------- Cleaning brush*1

------------------------ 3.5/4.4mm swappable plugs*1

----------Red/Black swappable sound nozzles*2 pairs

------------------------------------ Quick start guide*1

Visibly great,

audible awesome

Cut through the markups and get access to affordable high-quality cables. Since being featured with the FT3, cables made from Furukawa’s high-purity monocrystalline copper have been sought after by audiophiles around the world. The new FD15 also uses these cables, and comes standard with a Furukawa monocrystalline silver + Furukawa monocrystalline silver-plated copper braided cable. The cable consists of four large strands, each made up of 100 copper wires and 20 silver-plated wires for an overall total of 480 wires, which is unparalleled in its class. With a cross-sectional area of 22AWG and having undergone 1050°C high-temperature smelting, the included cable is truly of high-end quality but at an affordable price.

0.08mm Furukawa monocrystalline silver

0.05mmFurukawa monocrystalline   silver-plated copper braided headphone  cable


MMCX connector

Expanded MMCX is better reinforced, for more stable connections

Coaxially braided

0.08mm*20 strands of Furukawa silver-plated copper 0.05mm* 100 strands of Furukawa monocrystalline silver

*This cable is identical to LC-RC 2024.

The FD15 is available in obsidian black and racing silver, two stylish colors for  you to choose from. Obsidian black: Subtle yet elegant, a true stable classic Racing silver: Always moving like quicksilver, with thunderous momentum

Looks can be important Two colors available

With  the FD15, gain  access to  more sound profiles. The FD15 comes with two pairs of swappable sound nozzles, allowing you to customize the sound to your tastes and music preferences.

Multiple flavors, choose to your taste 2 swappable sound nozzles

 *The above data comes from FIIO Lab.

Black sound nozzle——enhances high frequencies, making it easier to pick out details, for genuinely clear treble.

Furukawa monocrystalline silver + Furukawa monocrystalline silver-plated copper braided headphone cable

Straight twist-lock swappable audio plug

Supports 3.5/4.4mm plugs

*Swappable audio plug patent licensed from FABRILOUS

Secondary refinement

process Heating to melting point at 1050°C Isothermal sintering for 744 hours Over 70 complex processes

 *The above data comes from FIIO Lab.

Red sound nozzle——enhances bass, gives lusher vocals, and overall a more emotional experience.

Basic specifications

Earphone type:  Dynamic in-ear monitors

Wearing style:  in-ear and around-the-ear

Driver:  aluminum-magnesium dynamic driver

Frequency response:  10Hz-40kHz

Impedance:  32Ω@1kHz

Sensitivity:  112dB/mW@1kHz

Cable:  4 strands totaling 480 wires of hybrid silver

           and Furukawa monocrystalline copper wires

Cable length:  about 1.2m

Single unit weight:  about 12g (excluding cable)

Earphone connector:  expanded MMCX

Audio plug:  straight twist-lock swappable plug
Two colors available:Obsidian Black/Racing Sliver