Mofi Electronics MasterDeck + black

Forty years of turntable design condensed into a single device. Allen Perkins, who worked at SOTA, Immedia, and Spiral Groove before becoming chief analog engineer at MoFi Electronics, designed the MasterDeck as the synthesis of everything he has learned about vinyl playback: bearings, drive systems, tonearms, material choices. The “+” version comes with the UltraGold MC moving coil cartridge pre-installed and factory-aligned, ready to use.

A Massive Plinth Built in Ann Arbor

Every MasterDeck is assembled in small batches at the MoFi factory in Ann Arbor, Michigan. The base rests on a constrained-layer structure: an MDF body topped with two bolted aluminum plates, the whole dressed in a solid wood frame (walnut or black ash, your choice). The idea is straightforward: materials of different densities and rigidities brake each other and dissipate residual vibrations before they reach the groove.

The turntable weighs 17 kg. It makes no pretense of being light: when you lift it, you understand that mass is part of the design brief. Under the plinth, four feet developed with Harmonic Resolution Systems (HRS) offer 5.5 degrees of freedom and effectively “float” the turntable on its stand, isolating it from external vibrations and acoustic feedback. The MasterDeck does not come with a dust cover, which may come as a surprise at this price level, but the choice is justified by the desire to eliminate any additional source of resonance.

Hybrid Platter and Spiral-Groove Bearing

The 44 mm thick platter weighs 6.5 kg. It consists of an aluminum core coated with Delrin (polyoxymethylene), a crystalline polymer whose acoustic impedance is close to that of vinyl. This aluminum/Delrin combination combines the inertia of aluminum (rotational stability) with the damping of Delrin (resonance absorption). The resulting noise floor is very low: the micro-details buried in the groove emerge effortlessly.

This platter spins on an inverted encapsulated spiral-groove bearing, a design derived directly from Perkins’ Spiral Groove turntables. The materials used (stainless steel, bronze, precision steel ball, Teflon thrust pad) are housed in a sealed aluminum housing. Friction is minimal, wear is very low, and rotation is remarkably smooth. Perkins has been using this type of bearing since 1991; the MasterDeck version is its most refined iteration to date.

Belt Drive with Optical Speed Regulation

The motor is a brushless sinusoidal three-phase model, housed in an isolated enclosure to prevent any transmission of vibrations to the plinth. The rubber belt (in MoFi’s characteristic orange hue) drives the platter at its periphery.

The speed regulation system is worth dwelling on. At startup, an optical sensor measures the actual speed of the platter and adjusts the motor’s supply frequency until it reaches the target value (33.3333 RPM, for example). Once the speed is locked, the motor maintains it with the stability characteristic of synchronous motors. A four-digit digital display, located to the left of the platter, allows real-time speed monitoring. A fine-adjustment potentiometer (trim) allows subtle corrections, useful for records whose pressing deviates slightly from the nominal speed.

The MasterDeck plays all three standard formats: 33⅓, 45, and 78 RPM. The 78 RPM compatibility opens access to shellac collections, something most modern turntables do not offer.

A 10-Inch Carbon Dual-Pivot Tonearm

The tonearm is an original creation by Perkins, and it is one of the elements that most clearly distinguishes the MasterDeck from its smaller siblings the StudioDeck and UltraDeck (which use aluminum arms with conventional bearings). Here, the tube is made of carbon fiber with an internal taper that enhances rigidity while damping resonances. Its 10-inch (254 mm) length reduces tracking errors compared to the 9-inch arms typically found in this price range.

The pivot mechanism is hybrid: a unipivot point supports the arm vertically, while two ruby balls ensure lateral stability. Perkins summarizes the principle as follows: the three contact points combine the fast energy transfer and stability of a gimbal with the tracking qualities of a unipivot. The result is an arm that is both stable and free in its movements, with near-zero friction.

The headshell is removable, secured by a threaded precision collar that holds it firmly while facilitating azimuth adjustment (simply rotate the headshell on its axis). The internal wiring, supplied by Cardas Audio, runs continuously from the cartridge pins to the RCA connectors, with no intermediate connection points, even at the removable headshell. Available adjustments cover all parameters: arm height (VTA), azimuth, overhang, tracking force, and anti-skating (via thread and counterweight).

The arm accepts cartridges weighing between 5 and 14 g, covering a wide portion of the market, from lightweight MC cartridges to heavier models.

The UltraGold MC Cartridge: From Groove to Signal

The “+” version of the MasterDeck includes the UltraGold MC cartridge, the highest-resolution model in the MoFi catalog. Manufactured in Japan and voiced by Allen Perkins, it is a moving coil (MC) cartridge fitted with a nude Shibata stylus mounted on a boron cantilever.

Some useful specifications: output voltage of 0.4 mV (an MC phono preamplifier is essential), bandwidth from 20 Hz to 35 kHz, recommended tracking force between 1.8 and 2.2 g, minimum load impedance of 100 Ohms. The body is a hybrid housing of extruded aluminum and brass, designed to minimize parasitic vibrations. The magnet is neodymium, with a permendur pole piece (an iron-cobalt alloy with very high magnetic permeability). The threaded body allows quick mounting with two screws, with no nuts or bolts required.

The factory alignment of the cartridge on the MasterDeck arm is a genuine advantage: the arm/cartridge geometry has been jointly optimized, eliminating the guesswork of manual mounting. That said, all adjustments remain accessible for personal fine-tuning.

From the StudioDeck to the MasterDeck: What Has Changed

For users already familiar with MoFi turntables, the MasterDeck differs from the UltraDeck on several points. The arm moves from aluminum to carbon fiber, with a completely redesigned pivot mechanism. The platter gains in thickness (44 mm vs. 33 mm) and mass (6.5 kg vs. 3 kg), and incorporates an aluminum core absent from the UltraDeck. The motor moves from a stepped-pulley synchronous model to one regulated by an optical sensor. 78 RPM playback is added, along with fine speed adjustment and digital display. The bearing adopts the encapsulated Spiral Groove design. The HRS feet are a step above those of the UltraDeck.

The footprint remains comparable (50.8 × 38.4 cm) and the height is moderate (13 cm without the arm), but the weight increases from 11 to 17 kg.

Setup and Practical Considerations

The MasterDeck requires some care during installation. The support furniture must be stable and level: the HRS feet are height-adjustable, but they work best on a flat, rigid surface. MoFi recommends performing speed calibration with a record on the platter, the record clamp in place, and the stylus in the groove, so sensitive is the system.

The arm offers a wide range of adjustment, but this versatility requires a slightly longer setup time than a fixed arm. The cueing lever, slightly longer than average, makes stylus placement easier. The thread-and-counterweight anti-skating is precise, but slightly more delicate to adjust than a magnetic system.

Technical specifications

Drive system and operation

• Drive system: optically regulated synchronous DC belt drive
  • Ultra-stable speed
  • Elimination of pitch variations
  • Extreme rhythmic precision
• Speeds: 33 ⅓ / 45 / 78 RPM with fine adjustment (trim)
• Power consumption: < 5 W
• Encapsulated inverted spiral bearing
  • Ultra-smooth rotation
  • Minimal friction
  • Increased longevity and precision

Platter

• Delrin / aluminum hybrid platter
  • Thickness: 1.75” (≈ 44 mm)
  • Weight: 6.5 kg
  • Maximum inertia
  • Reduced resonance
  • Extremely quiet background noise

Tonearm

• 10” dual-pivot carbon tonearm (hybrid unipivot / gimbal)
• High-rigidity carbon fiber
• Near-zero friction
• Ultra-precise groove tracking for maximum extraction of musical information
• Removable headshell
• Internal Cardas Audio wiring
• Full adjustments: VTA, azimuth, overhang, anti-skating
• Compatible cartridges: 5 g – 14 g

Included cartridge

• Pre-installed UltraGold MC (Moving Coil) cartridge
  • High-output Moving Coil technology
  • High-precision factory alignment
  • Maximum resolution level in the MoFi range
  • Exceptional micro-dynamics
  • Expanded and holographic soundstage
  • Extreme micro-detail
  • Optimized synergy with the MasterDeck tonearm

Isolation and structure

• HRS isolation developed with Harmonic Resolution Systems
  • Total vibration decoupling
  • Absolute mechanical stability
• Ultra-rigid structure made in the USA

Dimensions and weight

• Dimensions (W × H × D): 50.8 × 13.0 × 38.4 cm
• Weight: 17 kg

Sound signature

• Reference-level resolution
• Extremely stable 3D soundstage
• Deep, fast, controlled bass
• Midrange with striking realism
• Detailed and airy highs
• Near-absolute silence between notes

Key strengths

• Ultra high-end version with UltraGold MC cartridge
• 33 / 45 / 78 RPM playback with fine speed adjustment
• Ultra-precise dual-pivot carbon tonearm
• Very high-inertia hybrid platter
• Optically regulated DC drive system
• High-level HRS isolation
• Ultra-rigid structure made in the USA
• Maximum resolution and dynamics in the MoFi range