Opus4

Opus4 is a moving iron phono cartridge with an American Maple wood body. It is the starting point of the Timbre Series and uses Grado's flux-bridger principle, which keeps the coils fixed and the moving mass very low. The sound is described as balanced and controlled, with a warm midrange, defined bass and a smooth top end.

The stylus is a bonded elliptical diamond on an aluminum cantilever. Internal wiring uses 5N OCC copper, and each cartridge receives cryogenic treatment and internal damping to limit resonance. The wood housing is chosen to help control resonance across a range of tonearms.

It is built in high-output (4.0 mV) and low-output (1.0 mV) versions so it can work with a wide range of phono stages, and in mono high- and low-output special-order versions. It is insensitive to capacitive load, with a recommended input load of 10k-47k ohms. Owners of other Grado wood cartridges can use the maker's Wood Cartridge Upgrade Program.