Mofi Electronics MasterDeck + walnut

Forty years of turntable design condensed into a single machine. 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 preinstalled and factory-aligned, ready to use.

A massive plinth made in Ann Arbor

Each MasterDeck is assembled in small batches at MoFi’s factory in Ann Arbor, Michigan. The base is built on a constrained-layer structure: an MDF body topped with two bolted aluminum plates, all wrapped in a solid wood frame (walnut or black ash, your choice). The idea is simple: materials with different densities and stiffnesses counteract one another and dissipate residual vibrations before they reach the groove.

The turntable weighs 17 kg. It does not pretend to be 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) provide 5.5 degrees of freedom and “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 be surprising 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 covered 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 quiet: the micro-information buried in the groove comes through effortlessly.

This platter spins on an inverted encapsulated spiral-groove bearing, a design directly derived from Perkins’s Spiral Groove turntables. The materials used (stainless steel, bronze, precision steel ball, Teflon thrust plate) are housed in a sealed aluminum enclosure. 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 accomplished iteration to date.

Belt drive with optical regulation

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

The speed regulation system deserves a closer look. At startup, an optical sensor measures the platter’s actual speed and adjusts the motor’s power frequency until it reaches the target value (33.3333 rpm, for example). Once the speed is locked, the motor maintains it with the stability typical of synchronous motors. A four-digit digital display, located to the left of the platter, lets you view the speed in real time. 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, which most modern turntables do not offer.

A 10-inch carbon tonearm with dual pivot

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

The pivot mechanism is hybrid: a unipivot point supports the arm vertically, while two ruby balls provide lateral stability. Perkins sums up the principle this way: 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 making azimuth adjustment easier (you 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. The available adjustments cover all parameters: tonearm height (VTA), azimuth, overhang, tracking force, and anti-skate (via thread and counterweight).

The arm accepts cartridges from 5 to 14 g, covering a large part 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 most resolving model in the MoFi catalog. Made 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.

A few useful figures: 0.4 mV output voltage (an MC phono preamplifier is essential), frequency response 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 enclosure in extruded aluminum and brass, designed to minimize parasitic vibrations. The magnet is made of neodymium, with a permendur yoke (an iron-cobalt alloy with very high magnetic permeability). The threaded body allows quick mounting with two screws, without nut or bolt.

Factory alignment of the cartridge on the MasterDeck arm is a real advantage: the arm/cartridge geometry has been jointly optimized, avoiding the trial and error of hand mounting. That said, all adjustments remain accessible for personal fine-tuning.

From StudioDeck to MasterDeck: what has changed

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

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

Setup and practical considerations

The MasterDeck requires a bit of 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, as the system is that sensitive.

The arm offers a great deal of adjustment latitude, but this versatility means a slightly longer setup time than with a fixed arm. The cueing lever, slightly longer than average, makes lowering the stylus easier. Thread-and-counterweight anti-skate is precise, but a bit more delicate to adjust than a magnetic system.

Technical specifications

Motor and drive

• Motor: 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

• Hybrid Delrin / aluminum 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
• Cardas Audio internal wiring
• Full adjustments: VTA, azimuth, overhang, anti-skating
• Compatible cartridges: 5 g – 14 g

Included cartridge

• Preinstalled 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, 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
• Strikingly realistic midrange
• Detailed, airy treble
• Near-absolute background silence

Highlights

• 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 motor
• High-level HRS isolation
• Ultra-rigid structure made in the USA
• Maximum resolution and dynamics in the MoFi range