Головки звукоснимателя — MoFi Electronics MASTERTRACKER MM PHONO

The MasterTracker is a high-output MM phono cartridge made by MoFi Electronics, developed by the Mobile Fidelity design team together with Allen Perkins, founder of Spiral Groove. MoFi states that the design was engineered to mirror the cutting-head equipment used in the Mobile Fidelity studio in Sebastopol, California. It sits in a MoFi moving-magnet line that also includes the StudioTracker and the UltraTracker.

Key specs that matter

Frequency response is 20 Hz to 25 kHz. MoFi recommends a load of 47 kOhm and a capacitance of 100 pF. Static compliance is 40 x 10-6 cm per dyne and dynamic compliance is 10 x 10-6 cm per dyne. Channel separation reaches 27 dB at 1 kHz, with channel balance held within 1.0 dB at the same frequency. The cartridge weighs 9.7 g. Tracking force lies between 1.8 and 2.2 g, with 2.0 g given as the recommended figure.

Engineering and use context

MoFi uses a V-Twin dual-magnet generator here, with two low-mass, powerful magnets set in a V formation parallel with the record grooves, moving past coils wound from pure Ohno continuous-cast copper. This layout copies the geometry of the lathe head that cuts the lacquer, and MoFi credits it with high channel separation and precise groove tracking. The diamond is a trademarked Micro-Line profile shaped like the cutting head of a record lathe, intended to trace the microscopic features of the groove walls and mounted at the end of a tapered cantilever made of aluminium. The dark grey housing is CNC-milled from a solid billet of 6061 aluminium in the USA, and the cartridge is then assembled by hand in Japan. MoFi describes the body as well damped, with resonance-damping materials used to control resonances within the cartridge, and states that the MasterTracker carries the lightest magnets of any model in its Tracker Series.

Pairing

The body has threaded screw holes, so it bolts to a headshell without loose nuts, and the underside sweeps upward to leave a clear view of the stylus during installation and alignment. A protective stylus guard is supplied. The cartridge is specified as compatible with most modern tonearms, and as a moving-magnet design it works into the standard MM input of a phono preamplifier.

Alternatives

The MoFi UltraTracker is another moving-magnet model in the Tracker Series, pairing the V-Twin dual-magnet generator with a nude elliptical diamond, an aluminium cantilever and a rated output of 3.5 mV.