Grado Opus4 Phono Cartridge

A Timbre Series moving iron cartridge with American Maple wood body, bonded elliptical diamond, and aluminum cantilever

The Grado Opus4 is the entry point into Grado’s Timbre Series, introducing the tonal character and construction of Grado’s wood-body cartridges. It uses an American Maple wood body chosen to help control resonance and contribute to the cartridge’s tonal balance.

Like all Grado cartridges, the Opus4 is built around a moving iron design based on Joseph Grado’s patented flux-bridger principle. This keeps the coil structure fixed while using low moving mass to generate the signal, giving the cartridge a combination of speed, control, and long-term consistency.

The Opus4 uses a bonded elliptical diamond mounted to an aluminum cantilever, with an internal signal path made from ultra-high purity 5N OCC copper. Each cartridge also undergoes cryogenic treatment and internal damping to help reduce unwanted resonance and preserve signal integrity.

High-Output, Low-Output, and Mono Builds

Opus4 is available in high-output and low-output stereo versions, allowing compatibility with a wide range of phonostages. Mono high-output and mono low-output versions are also available as special-order builds.

Moving Iron Design

Grado’s moving iron architecture is designed to combine the low moving mass often associated with moving coil cartridges with the practical stability of a fixed-coil design. The result is a cartridge intended to deliver clarity, separation, and tonal integrity without requiring a fragile moving coil assembly.

Diamond and Cantilever

The bonded elliptical diamond provides effective groove contact and reliable tracking, while the aluminum cantilever contributes to a stable and controlled presentation. This pairing supports the Opus4’s clarity, balance, and smooth top end across a wide range of recordings.

Wood Body Construction

The American Maple wood body gives the Opus4 its distinctive appearance while helping manage resonance. The structure supports stable playback and consistent performance across a wide range of tonearms.

Specifications

Body: American Maple wood

Generator Type: Moving iron

Cantilever and Stylus: Aluminum cantilever with bonded elliptical diamond

Output (High, Low): 4 mV, 1 mV

Inductance (High, Low): 55 mH, 6 mH

Resistance (High, Low): 660 Ω, 70 Ω

Input Load: 10 kΩ–47 kΩ

Tracking Force: 1.6 g–1.9 g

Compliance: 20 µm/mN

Channel Separation: Average 30 dB, 10 Hz–30 kHz

Controlled Frequency Response: 10 Hz–60 kHz

Weight: 8.3 g