The SPU Mono CG 25 Di MkII is for the playback of early 25 µm mono recordings.

The Mono CG 25 Di MkII is an SPU-style Moving Coil cartridge with a spherical stylus profile, for the playback of early 25 µm mono recordings. The CG 25 Di MkII provides an authentic method of playing back these early vinyl recordings with a remarkable level of sonic accuracy.
This cartridge features a 1.5mV output, which makes it suitable for use with a variety of medium-gain moving coil transformers. Ortofon ST-M25 moving coil transformer is designed exclusively for the SPU Mono CG 25 Di MkII.

Technical data

Output voltage at 1000 Hz, 5cm/sec. - 1.5 mV
Frequency response - 20-15.000 Hz + 3/- 1 dB
Tracking ability at 315Hz at recommended tracking force *)  > 60 µm
Compliance, dynamic, lateral - 7 µm/mN
Stylus type - Spherical
Stylus tip radius - R 25 µm
Tracking force range - 3.0-4.0 g (30-40 mN)
Tracking force, recommended - 3.5 g (35 mN)
Tracking angle - 20°
Internal impedance, DC resistance - 6 ohm
Recommended load impedance  > 100 ohm
*) Typical value

Cartridge body material - Ground wood and resin composite
Coilwire material - High Purity Copper (OFC)
Cartridge colour - Black matte
Cartridge weight - 35 g