20-12 MKII

The SME 20-12 MKII is a suspended turntable for analogue playback, and the larger development of the SME Model 20/2. It accommodates 9-, 10- and 12-inch tonearms, with particular emphasis on the Series 300 Model 312S.

The 312S uses a magnesium pressure-die-cast wand and headshell, combining rigidity with low mass and reducing weight by 27g compared with aluminium. Its 12-inch geometry reduces angular-error distortion by approximately 27% compared with a typical 9-inch arm, contributing to low tracking and harmonic distortion.

SME applies the same principles of mass, rigidity and controlled damping to the Model 20/12 turntable. The approximately 33.5kg construction incorporates a 16mm-thick, 8kg sub-chassis measuring 520 x 375mm. Its structural mass and extensional damping reduce flexing and resonance, creating a stable platform for record playback.

The sub-chassis is suspended on 40 purpose-moulded O-rings to isolate it from acoustic feedback. A centrally positioned fluid damper controls sub-chassis movement, while the structural interfaces manage the transfer and dissipation of unwanted acoustic energy. This vibration-control system supports tonal neutrality, dynamic precision and resolution, allowing the character of the original recording to emerge with minimal interference.

The Model 20/12 is available in 2 formats.

MODEL 20/12
Equipped for but not including a pick-up arm.

MODEL 20/12A
As above but fitted with Series 300 Model 312S precision pick-up arm.

Dimensions: 520 x 375 x 173.5mm.
Packing: Substantial case.
Net weight with power supply: 35.5kg (78lb)
Shipping weight approximately: 45.5kg (100lb)

The graph compares angular error distortion between typical 9-inch and 12-inch arms, with null points selected to equalise distortion at maximum and minimum recorded diameters.

• Stable four point suspension.
• Sub-chasis suspended on eighty strands of rubber in the form of forty purpose moulded ‘O’-rings.
• Trimming screws for suspension adjustment.
• Central fluid damper controls sub-chassis motion and offers resistive ground-path for acoustic signals.
• For transport lock down screws secure the sub-chassis and seal the damper.
• 19mm diameter main spindle machined from high-chrome steel hardened, ground and super finished. Runs in a sealed oil bath.
• Reflex clamping system minimises record resonance.
• 6.5Kg (14.3lb) machined platter with unique Isodamp face.
• Generous use of extensional damping and resistive loop construction ensure sonic neutrality.
• Adjustable ball feet with optional compliant inserts.
• Four jacking screws built into the sub-platter allow the thrust bearing to be off loaded for transit.
• Driven by a 3-phase, 6 pulse, inductance motor, with 8 pole Neodymium magnets and 3 integrated Hall position sensors.
• The power supply houses an electronic controller using a high performance microcomputer, optimised for motor control. Closed loop speed control is implemented using a pseudo sine wave commutation sequence and a proportional-plus-integral (PI) algorithm.
• New design incorporates a 4 layer surface mount technology pcb with on-board user adjustable speed variation control.
• Large diameter strobe disc supplied allows precise adjustment of standard speeds.
• Speeds ranges: 33.3, 45 and 78 rpm.