Thats interesting-A DC stepper type motor-almost sounds like a giant version of the DC brushless pulsed motor used in Technics DD Turntables-same idea.Alter the pulses and the motor oscillates instead of rotating.However think I would rather stick with the traditional AC induction motor,belt and transmission.The Technics TT motor is also miniature 3Ph DC pulsed motor.The PM rotor is on the bottom of the platter-the stator in the TT base,along with the electronics.