Mobile Fidelity MasterDeck Turntable

The Mobile Fidelity MasterDeck turntable is designed in the US, by Allen Perkins. The turntable is a high-end unit that is intended to bring the sound of the master tape into your home. Notably, the carbon fibre tonearm is a unique 10” design with a “zero gap” uni-pivot bearing as well as a standard gimbal. This is intended to give extra precision, control, and tracking.

The counterweight has a patented spiral groove, and the arm has a removable headshell. Next, there is both a VTA and azimuth adjustment so that you can use virtually any cartridge. Unusually this is a three-speed unit with a digital display of the speed. Moreover, there is also a very precise motor control system.

The ultimate tonearm?

The carbon fibre tonearm, used by the Mobile Fidelity MasterDeck has virtually every imaginable adjustment. Firstly it is longer than the usual 9” at 10”. This is thought to improve the tracking accuracy. The arm also sits on a combination of uni-pivot and a standard gimbal. Uni-pivot bearings sit on the head of a needle, for low resistance while gimbal types have good stability. The counterweight also has a spiral groove that helps to set the tracking weight accurately. Finally, both azimuth and VTA adjustments are provided.

What is VTA and azimuth?

The Mobile Fidelity MasterDeck has both VTA and azimuth adjustments. Vertical Tracking Angle or VTA is the angle at which the tonearm meets the record surface. This is not actually supposed to be 90 degrees. Records are cut at a slight angle of 20 degrees. Hence the VTA should be set to this value. Different cartridge heights can affect this. Notably, incorrect VTA can increase distortion and groove wear. Azimuth refers to the vertical angle of the stylus in the groove. If this is incorrect the channel balance can be affected.

Platter and motor design

The drive motor used by the Mobile Fidelity MasterDeck is a three-phase brushless DC (BLDC) sinusoidal type. The motor is isolated in a container and features electronic speed control. Additionally, the turntable is a three-speed unit with fine adjustment. The speed is shown on a four-digit digital display. The motor drives a heavy 4.0cm thick Delrin-toped aluminium platter via a belt. The plinth itself is made of real wood with anti-vibration feet.

Cartridge types

The Mobile Fidelity MasterDeck has an accompanying top-of-the-line phono pre-amp. (supplied separately), this has both moving magnet and moving coil inputs, so a few words on cartridge types are in order. There are two main types of cartridges, moving magnet and moving coil. The Mobile Fidelity MasterDeck has a wide range of adjustments that can take full advantage of moving coil-type cartridges.

These have tiny coils mounted onto the cantilever that recover the audio. However, moving coil cartridges can have low output, sometimes less than 1mV. The MasterPhono pre-amp has switchable inputs so that MC cartridges can be used. The main advantage of moving coil cartridges is the lower mass of the stylus assembly. This is designed to improve tracking.