Fostex TH910 is Fostex's flagship next-generation closed-back dynamic headphone, launched in the second half of 2025 as the direct successor to the TH900mk2 and the closed counterpart to the TH919. The 50mm BioDyna mk2 driver features an updated voice coil and reinforced diaphragm surround at 1.5 Tesla magnetic flux density; the solid Japanese maple housing carries Urushi lacquer with a sulfur-smoked silver foil pattern — identical finishing technique to the TH919. The closed acoustic chamber differentiates the TH910 from the TH919 in terms of acoustic pressure, bass character, and isolation. Magnesium alloy mechanical components, mk2 earpads with a dual-layer silk protein and sheepskin leather configuration. Hand-assembled in Japan.
Closed chamber with BioDyna mk2 at 1.5 T: updated flagship driver in a closed-back architecture
The 50mm BioDyna mk2 transducer in the TH910 is the identical updated driver as in the TH919 — a new voice coil and reinforced diaphragm surround reducing distortion and bass artifacts while maintaining 1.5 Tesla magnetic flux density and the tonal character of the flagship line. The closed acoustic chamber builds pressure on the inner side of the earcup — combined with the precise acoustic path tuning of the TH910, this delivers a more intense, deeply anchored bass and a more focused soundstage than the TH919, alongside passive environmental isolation. The BioDyna diaphragm in bio-cellulose and composite fibers with a free-edge design. Frequency response: 12.5–40,000 Hz — identical to the TH919 and differing from the TH900mk2 (5–45,000 Hz), reflecting the housing tuning update of the new generation. Impedance: 25 Ω, sensitivity: 100 dB/mW, maximum input: 1,800 mW. Weight: approx. 385 g.
Japanese maple with Urushi lacquer and silver foil: Sakamoto craftsmanship and magnesium alloy in place of aluminium
The solid Japanese maple housing is finished with Urushi lacquer by the Sakamoto Otosho Shoten factory, established in 1900 — with a sulfur-smoked silver foil pattern applied in a torn-paper manner over a base black lacquer, creating a multi-layered depth unique to each individual unit. The TH910's finishing technique is identical to the TH919; the distinction is the closed acoustic chamber rather than an open one. Mechanical components including the base plate and yoke are machined from magnesium alloy — approximately 20% lighter than aluminium. Mk2 earpads: dual-layer foam with silk protein synthetic leather covered by natural sheepskin leather. Included cable: 2 m, 7N OFC, 6.3mm plug, 2-pin connector with rhodium-plated contacts on a gold-plated base. Balanced connection via the optional XLR cable (ET-H3.0N7BL) and 4.4mm cable (ET-TH4.4BL). Leather carrying pouch included.
KEY FEATURES
- Closed-back dynamic design — Fostex next-generation flagship dynamic headphone, successor to TH900mk2, closed counterpart to TH919
- 50mm BioDyna mk2 driver: bio-cellulose diaphragm, updated voice coil, reinforced surround, 1.5 Tesla
- Closed acoustic chamber — intense deep bass, focused soundstage, passive environmental isolation
- Solid Japanese maple housing + Urushi lacquer with sulfur-smoked silver foil (Sakamoto factory, est. 1900) — each unit unique
- Mechanical components: magnesium alloy — approx. 20% weight reduction vs. aluminium
- Mk2 earpads: dual-layer foam + silk protein synthetic leather + natural sheepskin leather
- Included cable: 2 m, 7N OFC, 6.3mm plug
- 2-pin connector with rhodium-plated contacts on gold-plated base
- Optional balanced cables: XLR ET-H3.0N7BL, 4.4mm ET-TH4.4BL (sold separately)
- Included accessories: leather carrying pouch
- Hand-assembled, manufactured in Japan
TECHNICAL SPECIFICATIONS
- Type: closed-back, over-ear, dynamic
- Driver: 50mm BioDyna mk2 (bio-cellulose + composite fibers), neodymium magnet, 1.5 T
- Frequency response: 12.5 Hz – 40,000 Hz
- Impedance: 25 Ω
- Sensitivity: 100 dB/mW
- Maximum input power: 1,800 mW
- Weight: approx. 385 g (without cable)
- Housing: solid Japanese maple + Urushi lacquer with sulfur-smoked silver foil (Sakamoto); closed chamber
- Mechanical components: magnesium alloy
- Earpads: dual-layer foam + silk protein synthetic leather + natural sheepskin leather
- Included cable: 2 m, 7N OFC, 6.3mm plug
- Cable connector: 2-pin, rhodium-plated on gold-plated base
- Optional balanced cables: XLR ET-H3.0N7BL, 4.4mm ET-TH4.4BL
- Accessories: leather carrying pouch
- Manufacturing: hand-assembled in Japan
