Головки звукоснимателя — MoFi Electronics ULTRAGOLD MC PHONO

The UltraGold MC from MoFi Electronics is a moving-coil cartridge of the low-output kind, precision-built in Japan under strict quality-control measures. Its voicing was carried out by Allen Perkins, the founder of Spiral Groove. MoFi lists it alongside the StudioSilver MC and three moving-magnet designs in its current cartridge range, all developed in collaboration with Perkins. The US price is USD 1,495.

Key specs that matter

MoFi specifies a dual moving-coil stereo generator. Its nude Shibata diamond is carried by a boron cantilever, while PCOCC copper, short for Pure Copper by Ohno Continuous Casting, is used for the coil windings. Rated output is 0.4 mV at 5 cm per second, with a frequency response of 20 Hz to 35,000 Hz. Internal impedance is 12 ohms. MoFi quotes two compliance values - a static figure of 40 x 10e-6 cm per dyne and a dynamic figure of 10 x 10e-6 cm per dyne. Recommended tracking force is 1.8 to 2.2 g, and the cartridge weighs 7.3 g.

Engineering and use context

A neodymium magnet works with a permendur yoke to build the magnetic field around the coils. The housing is a hybrid of an aluminium extrusion and brass. The aluminium body carries threaded inserts, so the cartridge fixes to a headshell or an integral tonearm with just two screws and no separate nuts or bolts. The threaded mounting means no loose hardware has to be held in place while the cartridge is aligned, which MoFi presents as a way to simplify analogue setup. Besides being sold on its own, the UltraGold is offered factory-installed on the MoFi UltraDeck turntable as a ready-to-play package, sold under the UltraDeck +UG name at USD 2,499, with no mounting work left for the owner.

Pairing

With its low output, the UltraGold MC needs a phono stage offering proper moving-coil gain, via an active high-gain input or a step-up transformer, and the manufacturer calls for a load of 100 ohms or higher. MoFi's own UltraPhono Pro provides a 100 ohm loading position and up to 65 dB of gain on its RCA outputs or 71 dB on its balanced outputs, well above the coil impedance. On the separately sold StudioDeck the tonearm accepts cartridges from 5 g to 10 g, a window that includes this model.

Alternatives

The second moving-coil model MoFi offers is the StudioSilver MC, pairing a nude MicroLinear stylus with a boron cantilever and an output of 0.35 mV.