AC synchronous motor, belt drive, 16, 33 and 45 rpm, electronically switched, pitch +/- 2%, platter weight 3.2 kg (with subplatter), platter and armbase suspended by three-spring-subchassis, manual operation.

Rabco arm (see photo below), self cancelling, tangential tracking

cartridge not included, original service manual included (16 pages)

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Thorens TD 125 Mk II Turntable

" unquestionably one of the elite among record players. It would be hard to imagine a unit that performs better"

Equally as superlative is the laboratory testing report from High Fidelity..."All told the TD 125...shapes up as the best three speed manual we've yet tested".

Solid State Circuitry- A Key Component

The TD 125 MkII turntable is fitted with a Solid State Control System. This replaces the mechanical linkage which is normally necessary to maintain different record speeds. The Solid State Control Circuit consists of a Wien bridge oscillator, normally used in measuring instruments, and the frequency of this oscillator can be varied in definite steps so that the speed of the 16 pole synchronous motor can be changed. An additional fine frquency adjustment may be effected by means of a potentiometer, thus providing an electronic speed control within the the range of ± 2%.
The necessary power for the synchronous motor is produced by two identical push-pull amplifiers, one integrated in the Wien-bridge oscillator, the other driven via a resistor-condenser network, to maintain the necessary 90° phase shifts between the output signals.
Two integrated operational amplifiers (ICs) deliver the necessary voltage amplification, while the output stages are equipped with 4 silicon power transistors.
Thus the speed of the synchronous motor is controlled by the generated frequency. The desired record speed will be provided by the precise frequency variation of the control generator

Reduced Motor Speed Suppresses Rumble

Motor rotor speed has been reduced to an incomparable 250 rpm at 33 1/3 rpm turntable speed. By combining this factor with solid state circuitry and the Wien Bridge oscillator Thorens has reduced rumble to an infinitesimal and inaudible -48db (-68db weighted) - less rumble than any other turntable on the market.