Koetsu Onyx Platinum Moving Coil Cartridge

A stone-body moving coil cartridge with silver-plated copper coil wiring, platinum magnet, boron cantilever, and 0.3 mV output

The Koetsu Onyx Platinum sits among Koetsu’s stone-body cartridges, with a body machined from a carefully selected block of onyx and polished to a very fine finish. The stone body gives the cartridge a substantial physical foundation while preserving the distinctive beauty and individuality of the natural material.

Internally, the Onyx Platinum uses tightly matched silver-sheathed copper coils and cores, with a rare platinum magnet and boron cantilever. It is built to carry forward Koetsu’s reputation for color, texture, touch, and musical nuance.

With 0.3 mV output, 12.5 g net weight, and a recommended tracking force of 1.8 g–2 g, the Onyx Platinum is intended for serious analog systems with a tonearm, phonostage, and setup capable of realizing what a Koetsu stone-body cartridge can do.

About the Brand

Koetsu phono cartridges trace their lineage to Yosiaki Sugano, an artist, musician, calligrapher, swordsman, and business executive whose passions shaped one of analog audio’s most revered names. Inspired by the 17th-century Japanese artist Honami Koetsu, Sugano began experimenting with phono cartridges in the 1970s, combining a keen ear with an artist’s sensitivity to materials, proportion, and craft.

Koetsu cartridges remain deeply personal, hand-built creations, produced in limited quantities by the Sugano family. Their construction draws on carefully chosen materials and specialized craft, from ultra-pure conductors and precisely controlled magnetic parts to hand-carved wood, lacquer, and stone bodies. The result is a cartridge line valued not only for technical refinement, but for a distinctive musical character that has made Koetsu a lasting reference in high-end analog playback.

Specifications

Body: Onyx Stone

Type: Moving Coil

Coil Wiring: Silverplated Copper

Magnet: Platinum

Cantilever: Boron

Output: 0.3 mV

Recommended Tracking Force: 1.8 g–2 g

Recommended Load: 75 Ω–500 Ω

Weight: 12.5 g