Ortofon 2M 78 Premounted

Ortofon 2M 78 Premounted: The Ideal Cartridge for 78 RPM Records

The Ortofon 2M 78 Premounted is a mono phono cartridge specifically designed for playing 78 RPM records. It stands out for its ease of installation, being pre-mounted on Ortofon’s black SH-4 headshell. This “plug and play” configuration allows for direct and easy mounting on S-shaped tonearms without requiring complex adjustments.

The SH-4 headshell is characterized by its robust and rigid design, while sporting a slim and delicate shape. Lightweight and ergonomic, it features a long finger lift for easy handling. The precision assembly of the cartridge and headshell ensures optimal alignment for exceptional audio performance.

A Spherical Diamond Tip for 78 RPM Records

The 2M 78’s stylus is equipped with a spherical diamond tip with a 65 μm radius, specially designed for tracking the wide grooves of 78 RPM records. This larger diamond profile compared to classic stereo cartridges allows for precise groove tracking and faithful reproduction of vintage monophonic recordings.

An Optimized Motor for Authentic Sound Reproduction

Benefiting from Ortofon’s latest technological advancements, the 2M 78 features an improved generator motor offering a very high level of sound precision. Its output voltage of 4 mV at 1 kHz allows for extended compatibility with a wide range of MM phono preamps.

The cartridge body is made of Hopelex, a high-density polymer material that provides great rigidity while effectively eliminating unwanted resonances. The result: highly detailed and dynamic sound reproduction, free from distortion.

A Mono Cartridge for Optimal 78 RPM Playback

Unlike a classic stereo cartridge, the 2M 78 delivers an identical mono signal on both output channels thanks to parallel wiring. This configuration completely eliminates issues of crosstalk, phase difference, or distortion inherent in mono playback with a stereo cartridge.

Using a mono cartridge like the 2M 78 offers numerous advantages for listening to 78 RPM records:

• Total insensitivity to the vertical component of the groove, eliminating pinch effect in narrow grooves
• Significant reduction of surface noise, clicks, and pops related to groove wear and dirt
• Stable and precise sound image, free from phase issues
• More energetic and lively sound reproduction, with better focus

Key Advantages

• High-end mono cartridge optimized for 78 RPM records
• Plug-and-play mounting on SH-4 headshell for simplified installation
• 65 μm spherical diamond tip suited for wide 78 RPM grooves
• Improved generator motor for high sound precision
• Hopelex body eliminating unwanted resonances
• Parallel output for mono signal on both channels
• Detailed and dynamic reproduction, free from distortion
• Insensitivity to the vertical component of the groove
• Reduction of surface noise and wear-related defects
• Stable sound image with excellent focus
• Extended compatibility with numerous MM phono preamps

Technical Specifications

General Specifications

• Type: MM (Moving Magnet)
• Diamond: Spherical
• Output Voltage at 1,000 Hz, 5 cm/s: 4 mV
• Frequency Response: 20-20,000 Hz (+3, -1 dB)

Performance

• Tracking Ability (315 Hz at recommended tracking force): 70 μm
• Lateral Dynamic Compliance: 18 μm/mN
• Diamond Tip Radius: R 65 μm
• Tracking Force Range: 1.6-2.0 g (16-20 mN)
• Recommended Tracking Force: 1.8 g (18 mN)
• Tracking Angle: 20°

Electrical Characteristics

• Internal Impedance: 700 Ω, 1.2 Ω
• Internal Inductance: 350 mH, 630 mH
• Recommended Load Resistance: 47 kΩ
• Recommended Load Capacitance: 150-300 pF

Weight

• 2MR Cartridge: 6 g
• 2M and 2M Verso Cartridges: 7.2 g
• Pre-mounted 2M Cartridge: 16.7 g

Accessories

• Replacement Stylus: 2M 78 (interchangeable with 2M Mono)
• Supplied pre-mounted on an SH-4 headshell