SME Model 20 MK2 | Series V GPD

The MK2 Model 20 is a finely engineered precision turntable. High density construction, extensional damping of major
surfaces and lack of vibration from moving parts ensures exceptional detail, resolution and uncoloured performance.
Equipped with a new highly advanced drive system provides a significant improvement to speed control, accuracy and
stability, making the new generation Model 20 far superior to the highly acclaimed original.

The Model 20 has superb instrument quality machining allied with fundamental physics, the higher the mass and stiffness of the body the less it will flex and vibrate; the duration of a vibration is shortened by advanced damping treatment. The Model 20 effortlessly addresses the problems of extraneous vibrations which emanate from numerous sources including air and structural vibration from loudspeakers, groove modulation, stray electrical fields and mechanical energy from moving parts. Weighing 26kg is significant in relation to its size as density matters. The main and sub-chassis plate thicknesses are 16mm and resists flexing at low frequencies whilst high frequency resonance is attenuated by efficient extensional damping. The definitive performance Model 20 is available with or without a tonearm. The tonearm option is the flagship SME Series V with contrasting Silver Printed Detail and Crystal Cable internal wiring.

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.

DUMPING

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.