Grado Sonata 4 Moving Iron System

Grado Sonata 4

The Grado Sonata4 is part of the Timbre Series and combines high resolution with control and musical expression. Building on decades of experience in cartridge development, it consistently advances Grado's characteristic sonic philosophy. The moving-iron construction ensures a stable and responsive signal with exceptionally low moving mass.

The Sonata4 is available in stereo and mono versions, as well as with high output and low output, making it compatible with a wide variety of phono preamplifiers and tonearm designs.

Sound and performance

The Sonata4 is characterized by clarity, balance, and a natural musical flow. Fine details are precisely resolved without the treble losing any smoothness. The midrange impresses with presence and nuanced texture, while the bass is reproduced with control and clear definition.

Even complex recordings remain structured and coherent. Precise channel separation and stable spatial imaging ensure a convincing presentation of voices and instruments without artificially exaggerating the character of the music.

Moving iron technology

Like all Grado cartridges, the Sonata4 is based on the Flux-Bridger principle patented by Joseph Grado. In this system, an iron element with extremely low moving mass moves, while the coils remain fixed. This allows the system to generate a precise and stable signal while simultaneously reacting quickly to the subtlest modulations in the record groove.

The design combines speed and control with high harmonic integrity, enabling consistent playback over long periods of time.

Diamond and cantilever

The Sonata4 uses a nude elliptical diamond stylus mounted on a specially tuned aluminum cantilever. The elliptical profile enables precise contact with the record groove and detailed tracking.

The specially manufactured aluminum cantilever is tuned for balanced and responsive performance. The combination of diamond and cantilever supports clear, controlled, and natural sound reproduction.

High-purity 6N-OCC copper

The Sonata4's internal signal path consists of high-purity 6N-OCC copper. This material was chosen for its high conductivity and consistent properties.

Each pickup is also cryogenically treated and internally damped. This serves to reduce unwanted resonances and preserve the integrity of the audio signal.

Case made of Mediterranean olive wood

The Sonata4's housing is made of Mediterranean olive wood. This carefully selected wood supports resonance control and contributes to the cartridge's balanced tonal character.

The redesigned housing also improves the visibility of the stylus assembly during installation. This allows for more precise alignment of the Sonata4 and makes it compatible with a wide variety of tonearms.

Technical data

• Case: Mediterranean Olive Wood
• Needle carrier: special aluminum needle carrier
• 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: 9.4 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