Grado Master 4 Movin Iron System

Grado Master4

The Grado Master4 is part of the Timbre Series and combines decades of experience in cartridge development with Grado's characteristic sound philosophy. The cartridge focuses on a balanced, controlled, and musical reproduction, combining clarity and detail with a natural, organic sound.

Moving iron technology

Like all Grado cartridges, the Master4 is based on the Flux-Bridger principle patented by Joseph Grado. In this moving-iron design, a piece of iron with exceptionally low moving mass moves, while the coils remain fixed. This results in a precise and stable signal with high responsiveness and excellent control.

The design combines fast, dynamic reproduction with harmonic integrity while also contributing to the long-term reliability of the cartridge.

Sound and performance

The Master4 is characterized by a balanced and controlled sound reproduction. Fine details are rendered clearly and precisely, without any loss of naturalness in the treble range. The midrange is full-bodied and present, while the bass remains clearly structured and precisely defined.

Even with complex recordings, the Master4 maintains high stability and coherence. Channel separation and spatial imaging ensure precise reproduction of voices and instruments without artificially exaggerating the character of the recording. Instead of emphasizing its own sound, the Master4 allows each recording to retain its individual character.

The Master4 is available in both stereo and mono versions. Furthermore, high-output and low-output variants are available, allowing the cartridge to be combined with different phono preamps and amplifier designs.

Boron needle holder and diamond

A nude elliptical diamond stylus mounted on a precision-machined boron cantilever is used for tracking. The elliptical profile ensures precise contact with the record groove and highly detailed tracking.

The lightweight and rigid boron cantilever enables a fast and controlled response to the finest groove modulations. Combined with the low moving mass of the moving-iron construction, this results in precise, stable, and natural sound reproduction.

High-purity 6N-OCC copper

Grado uses high-purity 6N-OCC copper for the internal signal path. This conductor is chosen for its high purity and consistent electrical properties, ensuring the most accurate signal transmission possible.

Each pickup also undergoes cryogenic treatment and internal damping. This is intended to reduce unwanted resonances and preserve the integrity of the audio signal.

With its combination of moving-iron technology, boron cantilever, elliptical diamond and elaborately constructed internal components, the Grado Master4 consistently continues the tradition of Grado pickups with wooden bodies.

Technical data

• Cabinet: American Osage Wood
• Needle cantilever: manufactured boron needle cantilever
• Diamond: elliptical diamond
• Output voltage:
  • High Output: 4.0 mV at 5 cm/s (45°)
  • Low Output: 1.0 mV at 5 cm/s (45°)
• Inductance:
  • High Output: 55 mH
  • Low Output: 6 mH
• Internal resistance:
  • High Output: 660 Ohm
  • Low Output: 70 Ohm
• Recommended termination impedance: 10–47 kOhms
• Weight: 9.6 g
• Tracking force: 1.6–1.9 g
• Needle compliance: 20 µm/mN
• Channel separation: average 30 dB at 10–30 kHz
• Frequency range: 10–60 kHz
• Capacitance insensitive
• Versions: High Output, Low Output, Mono