SME Model 20/3A MK II Turntable (New boxed)

Construction.

The MK2 Model 20 is a precision turntable made to exacting engineering standards for high performance. The chassis and sub-chassis are CNC machined from premium grade aluminium billet and acoustically treated. The sub-chassis suspended suspension system provides definitive resonance control and houses the main bearing, platter and tonearm. Four fully adjustable feet are mechanically de-coupled from the main chassis by way of isolators.

The main spindle is 19mm in diameter, precision machined from high chrome tool steel, ground, super finished and supported in a sealed housing with individually fitted sintered bronze bearings of generous proportions needed for precise bearing and platter rotational control.

Suspension.

With no sonic footprint, the Model 20 sub-chassis is suspended on 40 purpose made suspension rings meeting all the requirements of high density construction, enabling a detailed resolution and uncoloured performance.

Damping.

A large central fluid-damper disciplines sub-chassis movement with a pleasing sense of security when handling records on the platter, offering a resistive ground-path for acoustic signals. In addition to a cartridge’s electrical output, mirror image acoustic signals reacted in the tonearm and record, will pass into the sub-chassis in the course of dissipation. However, the usual closed loop design does not address the problem of their differing phase, so in the Model 20 the structural interfaces concerned have received special attention to provide paths of the required impedance. This control of vibration is fundamental to the design of the Model 20 and goes a long way to explaining the stunning tonal and dynamic neutrality that it exhibits.

Platter.

The platter is machined from aluminium alloy and weighs 6.5kg. Extensionally dampened and the top surface iso-damp mat is diamond-turned with a fine scroll for acoustic performance. This method of finishing upsets a myriad of tiny fibres which interface with the underside of the vinyl record. A substantial record clamp operating on the reflex principle ensures the largest possible platter contact even when appreciable record warp is present.

Motor.

The Model 20 turntable is driven by a custom made bi-phase AC synchronous motor controlled by a highly advanced speed control unit providing precise speed accuracy and stability. The motor conforms to the highest standards of silent running.

Speed Control.

The Speed Control Unit uses a dedicated DSP engine to generate two independent pure mathematical sine waves which provide total control of frequency, phase relationship and amplitude. These in turn are matched (tuned) to the motor for accuracy to obtain the best possible performance. 

The speed range is 33.33 and 45 rpm with independent memory settings via a switched encoder. Fine pitch speed increments/decrements of +/-0.01% of the selected speed are made by a rotary control on the Speed Control Unit fascia. The SCU case is CNC machined from billet polymer resin with machined aluminium fascia, chassis base and rear panel.

Power Unit.

An independent mains Power Unit keeps the transformer separated from the Speed Control Unit and importantly away from the audio signal cables.

Dimensions & Weight.

Turntable
Width: 440mm
Depth: 350mm
Height (top of tonearm): 175mm
 
Speed Control Unit
Width: 150mm
Depth: 295mm
Height: 82mm
 
Power Unit
Height: 82mm
Width: 188mm
Depth: 242mm
 
Platter: 325mm
 
Weight
Turntable: 26kg
Power Unit: 4.04kg
Speed Control Unit: 2.52kg
Shipping Weight: 36.37

SME 20 Mk II Manual