Most people on this group are probably familiar with the concept of idler
wheel turntable drive. In this method, the circumferential surface of a
perfectly round wheel is coated with a compliant, elastic material, such as
rubber, having a high coefficient of friction. Solenoidal or lever actuation
of the wheel causes completion of a torque circuit between either a four
pole shadow motor, or, in high end equipment, an AC synchronous motor that
takes advantage of the inherent stability of the AC line. When the turntable
circumferential edge, the motor drive wheel, and the idler wheel are
machined with diamond tooled NC machinery, with final chamfering by an
experienced craftsman, the result can be said to be head and shoulders above
both belt and direct drive methods. Furthermore, the inherent simplicity of
the design permits user maintenance of virtually all aspects of the
instrument.

Stellar examples of this technique still exist in the rare and valued
members of the Garrard SL series, which embody both the highest tradition of
British craftsmanship, and a satisfying gleam and polish that strikes the
eye at virtually any angle. Even without the wonderment of the dual gimbal
suspension, the virtues would be inimitable. The dual gimbal suspension
elevates the highest member of this line, the Garrard SL95, to that of a
work of art.