B-Stock: Fostex TH818 Premium Open-Back Headphones with Kumiko-Inspired Aluminum Lattice Housing

The Fostex TH818 is the open-back sibling to the TH810, pairing the same 50 mm BioDyna driver with a matte anodized aluminum housing whose opening carries a geometric lattice motif drawn from kumiko, the traditional Japanese joinery art that assembles wood without nails. That grille is a precise two-layer laser-cut mesh structure.

Magnesium alloy is used for the housing base plate and hangers, natural sheepskin for the headband and head pads, and silk-protein synthetic leather for the ear pads. The result is a wide, natural soundstage with high resolution and clear instrument separation.

Kumiko-Inspired Aluminum Lattice

The open side of each housing is a matte anodized aluminum panel cut with a geometric lattice motif taken from kumiko, the centuries-old Japanese joinery craft that fits wood together without nails. The pattern is realised as a precise two-layer laser-cut mesh, so it functions acoustically as an open grille while carrying the visual reference.

Flagship 50 mm BioDyna Driver

The TH818 uses the same 50 mm neodymium BioDyna diaphragm driver as the closed-back TH810, reproducing 12.5 Hz to 45 kHz. In the open-back enclosure it trades the TH810's sealed low-end weight for a wider, more natural soundstage with clearer separation between instruments.

Magnesium Alloy Construction

The housing base plate and hangers are magnesium alloy rather than aluminum, cutting roughly 20 percent of the mass of the equivalent parts and suppressing unwanted vibration.

Sheepskin and Silk Protein Comfort

Natural sheepskin is used for the head pad and headband, while the ear pads use a silk-protein-based synthetic leather rated at roughly three times the durability of conventional synthetic leather.

Detachable 7N OFC Y-Cable

The supplied 2 m detachable Y-cable uses 7N grade (99.99999 percent) high-purity OFC conductors, with 3.5 mm 2-pole mini plugs at the earcups and a 6.3 mm gold-plated stereo plug at the amplifier.

B-stock may have minor cosmetic scratches or dents and furthermore B-Stock is not covered by full manufacturer warranty. Please call for details.

Product Specifications:

Type: Open-back, dynamic

Driver: 50 mm neodymium magnet, BioDyna diaphragm

Housing: Anodized aluminum with kumiko-inspired lattice opening

Impedance: 25 Ω

Sensitivity: 100 dB/mW

Maximum Input Power: 1,800 mW

Frequency Response: 12.5 - 45,000 Hz

Weight: Approx. 385 g (excluding cable)

Cable: 3.5 mm (2-pole) mini plug x2 (L, R) to 6.3 mm gold-plated stereo plug, 7N grade high-purity OFC, 2 m, detachable Y-cable

Accessories: Faux-leather pouch, safety precautions, quick start guide