Grado Red4 Hi-Fi Cartridge

Grado Red4 Phono Cartridge — Balanced Moving Iron Sound for Any Turntable

The Grado Red4 phono cartridge sits in the heart of the Prestige Series, delivering a balanced and engaging presentation built on decades of cartridge design experience. It maintains the core performance principles that define Grado cartridges while offering broad system compatibility. Built around the company's patented moving iron flux-bridger principle, this cartridge generates a precise signal with extremely low moving mass while keeping the coil structure fixed, avoiding the fragility often associated with traditional moving coil designs. The result is a presentation that combines speed, control, and harmonic integrity with long-term consistency.

Designed for compatibility with a wide range of phono stages, the Red4 produces a high-output 4 mV signal that drops into most MM phono inputs without the need for a step-up transformer. Its presentation is balanced and controlled, with clear detail and a smooth, natural top end, while the midrange carries presence and body and low frequencies remain defined and composed. Recordings come through with stability and coherence, maintaining separation and imaging while letting the character of the music speak for itself.

What Sets the Red4 Apart in the Prestige Lineup

Two construction details elevate this cartridge beyond a basic moving magnet design. The bonded elliptical diamond is mounted to an aluminum cantilever, pairing effective groove contact with a stable, controlled signal path that delivers clarity across a wide range of recordings. Inside, the internal wiring uses ultra-high purity 5N OCC copper selected for conductivity and consistency, and each cartridge undergoes cryogenic treatment and internal damping to reduce unwanted resonance. The user-replaceable stylus assembly makes long-term ownership simple, and all Prestige Series styli are interchangeable across models.

Signal Output and Phono Stage Compatibility

The output level of a phono cartridge determines which phono stages it can drive directly, and the Red4 is built for maximum flexibility in this category. A higher output means the cartridge can plug into standard moving magnet inputs without extra amplification, simplifying system matching.

• Output: 4 mV @ 5 CMV (45 degrees) — high enough to drive standard MM phono inputs directly.
• Input Load: 10k–47k ohms — compatible with the input impedance range of typical MM phono stages.
• Channel Separation: average 25 dB, 10–30,000 Hz — keeps stereo imaging stable across the audible band.

Frequency Range and Tracking Performance

Frequency response and tracking force together define how faithfully a cartridge reproduces the full range of a recording and how reliably it stays in the groove. Wide response and a moderate tracking window give the cartridge room to handle dynamic passages without distortion.

• Frequency Response: 10–55,000 Hz — extends well beyond the audible range for full-spectrum playback.
• Tracking Force: 1.6–1.9 g — moderate window that suits a broad range of tonearms.
• Compliance: 20 μm/mN — supports stable groove contact with typical medium-mass tonearms.

Build, Mounting, and Internal Construction

The physical design of a cartridge affects both its durability and how it integrates with a turntable. Housing material, mounting standard, and internal wiring all contribute to long-term reliability and consistent performance over years of use.

• Stylus: bonded elliptical diamond on aluminum cantilever — effective groove contact with a stable, controlled presentation.
• Cartridge Weight: 6 g — light enough for most medium-mass tonearms to handle comfortably.
• Mounting: P-mount or 1/2" screw mount — available in both configurations for broad system compatibility.
• Internal Wiring: ultra-high purity 5N OCC copper with cryogenic treatment — supports signal integrity and long-term consistency.

Who the Grado Red4 Is For

The Grado Red4 is the right choice for turntable owners who want a balanced, high-output moving iron cartridge that drops into a wide range of MM phono stages without extra hardware. Its 4 mV output suits listeners running standard integrated phono inputs, while the moderate 1.6–1.9 g tracking window and 20 μm/mN compliance make it a flexible match for many medium-mass tonearms. Available in both standard mount and P-mount, it accommodates classic screw-mount headshells as well as plug-in P-mount tonearms found on many entry-level and mid-range turntables. The user-replaceable stylus and interchangeable Prestige Series styli make it a practical long-term investment for vinyl listeners who want to refine their playback without rebuilding their entire system.

Grado Labs and the Prestige Series Heritage

Grado Labs has been hand-building phono cartridges in Brooklyn, New York, for decades, and the Prestige Series reflects that accumulated experience. Every cartridge in the line uses the company's patented moving iron flux-bridger design, an approach developed by founder Joseph Grado that pairs low moving mass with a fixed coil structure. The die-injection molded housing used across the Prestige Series supports consistent construction, while the user-replaceable stylus assembly and interchangeable styli across models give owners a clear upgrade path within the line.