Grado Opus3 The All New Timbre Series Opus3 cartridges offer a low mass generating system, and a diamond cut specially for Grado. The Opus3 is the first Grado cartridge to use a Maple housing, the Opus3 establishes a new entry point into the wooden Grado cartridge line with a price of just $275. The Timbre Opus3 uses a modified four piece OTL cantilever technology achieving a 10% tip mass reduction over the Prestige series and ultra-high purity long crystal (UHPLC) oxygen free copper wire in the coils. The Opus3 model uses Grado's specially designed elliptical diamond mounted on a brass bushing. The Timbre Opus3 cartridge is 1/2" mount. 78 RPM styli are not available with this cartridge. All re-tipping on the Timbre Opus3 series will be done through 4OurEars.