Dear @brunorivademar : You are biased to the EMT but you don't show yet facts that can probe what you " imagine ".
It's weird that the cutting lathe machines used DD servo units and not idler ones. Do you know why?, if you have the rigth answer mainly be for you.
@mijostyn Technics DD servo units were used in cutting lathe machines as the SP-02 that's similar ( with higher torque ) than the SP10MK3 even in some cutting lathe the SP10MK3 was used.
My favorite vintage DD is the Denon DP 100, I like that TT.
R.