Audio Technica AT33xMONO/I

The Audio-Technica AT33xMONO/I offers a refined approach to monophonic playback. Completely reengineered, this dedicated moving-coil cartridge leverages cutting-edge materials to reproduce the full density and texture of mono recordings, both vintage and contemporary. Designed for an authentic, highly dimensional presentation, it far outperforms a stereo cartridge merely used in mono mode.

True Mono design for pure lateral tracking

The fundamental feature of the AT33xMONO/I lies in its “True Mono” PCOCC coil configuration. Unlike stereo cartridges that capture both lateral and vertical groove movements, this cartridge generates an electrical signal solely from horizontal movements, precisely matching the way mono records were cut. The PCOCC (Pure Copper by Ohno Continuous Casting) copper coils are positioned horizontally at the cantilever’s pivot point, ensuring a pure, exclusive transmission of mono information.

This technical approach offers a major advantage: the cartridge naturally ignores the groove’s vertical components, whether surface noise, distortion, or wear-induced deformation. The result is mono reproduction of remarkable clarity, with a significantly reduced noise floor compared to a stereo cartridge playing a mono record. The signal-to-noise ratio is greatly improved, revealing musical details previously masked by interference.

The rigid duralumin tubular cantilever tapers toward the 16.5 μm (0.65 mil) conical diamond tip, optimizing frequency response and vibration transmission. This construction provides excellent rigidity while keeping moving mass low, enabling precise tracking of groove modulations with minimal distortion.

An innovative hybrid body to control resonances

The AT33xMONO/I debuts a groundbreaking cartridge body construction, combining three distinct materials in an optimized configuration. Die-cast zinc, used for the first time by Audio-Technica in a phono cartridge, delivers exceptional density and rigidity. This material, paired with aluminum and a high-rigidity polymer, forms a composite structure where each element plays a specific role in vibration control.

This multi-material approach disperses resonances throughout the cartridge body, preventing any single frequency from dominating during playback. Zinc absorbs low-frequency vibrations, aluminum manages the mids, while the polymer controls the highs. This strategic material distribution eliminates unwanted coloration and preserves tonal neutrality.

Threaded inserts integrated directly into the body greatly simplify mounting on the headshell or tonearm. No more juggling tiny nuts during installation: two screws are all it takes to secure the cartridge firmly, reducing setup time and the risk of damage.

A high-performance magnetic circuit

The magnetic core of the AT33xMONO/I combines a neodymium magnet with a permendur circuit, an iron-cobalt-vanadium alloy with exceptional magnetic properties. Neodymium offers particularly high magnetic energy density, while permendur provides superior magnetic saturation and optimal permeability, efficiently focusing magnetic flux in the gap where the coils move.

This technological combination generates a powerful, uniform magnetic field, allowing the PCOCC coils to produce a 0.42 mV electrical signal with remarkable linearity across the entire bandwidth. The concentrated magnetic force enhances fine detail resolution and dynamics, especially in complex passages where every nuance matters.

A redesigned suspension for broader compatibility

For the AT33x series, Audio-Technica developed a new suspension characterized by slightly lower dynamic compliance than previous models (6 × 10⁻⁶ cm/dyne at 100 Hz). This deliberate change greatly broadens compatibility with various tonearm types, from light models to medium- and high-mass arms.

Vertical compliance remains sufficient to ensure safe playback of stereo records, protecting your vinyl even in case of handling errors. This versatility is a major asset for collectors with a variety of pressings, both mono and stereo, allowing them to use the cartridge safely across their entire collection.

Japanese artisanal craftsmanship

Each AT33xMONO/I is hand-assembled by skilled artisans at Audio-Technica’s workshops in Japan. This meticulous manufacturing process ensures perfect alignment of critical components, including coil positioning and diamond orientation. Every cartridge undergoes rigorous quality control and individual adjustments before leaving the workshop.

This artisanal attention is reflected in consistent performance from one unit to the next, ensuring every user benefits precisely from the stated specifications. Handcrafting also allows precise control of PCOCC coil winding tension, optimizing sensitivity and frequency response.

Technical Specifications

General Information

• Type: true mono moving-coil dual-coil cartridge (MC True Mono)

Electrical Specifications

• Output voltage: 0.42 mV (1 kHz, 5 cm/s, horizontal signal)
• Coil impedance: 10 Ω (1 kHz)
• DC resistance: 10 Ω
• Recommended load impedance: ≥ 100 Ω (MC preamplifier)
• Inductance: 27 µH (1 kHz)

Mechanical Specifications

• Tracking force: 2.0 – 2.4 g (2.2 g standard)
• Static compliance: 14 × 10⁻⁶ cm/dyne
• Dynamic compliance: 6 × 10⁻⁶ cm/dyne (100 Hz)
• Stylus: 16.5 µm conical
• Cantilever: high-rigidity duralumin tube
• Vertical tracking angle: 20°

Performance

• Frequency response: 20 Hz – 30,000 Hz
• Horizontal/vertical channel separation: 25 dB (1 kHz)
• Channel balance: 1.0 dB (1 kHz)

Physical Specifications

• Dimensions (H × W × D): 16.1 × 16.6 × 26.1 mm
• Weight: 10.1 g
• Thread: M2.6 (built-in inserts)

Box Contents

• Non-magnetic screwdriver
• Cleaning brush
• Washers × 2
• Mounting screws: 2 × 8 mm, 2 × 10 mm, 2 × 13 mm
• Protective cap