I think it would be more accurate to say that optical cartridges respond to displacement, rather than to "position". It's the distance the stylus tip moves (for optical and strain gauge) vs the velocity at which it moves (for electromagnetic).
I apologize for the following, but what the heck, I am waiting for dinner: On p. 8, you wrote, referring to me, "Earlier in this thread you posted calculations giving the capacitance required to smooth various output voltages. With respect, your formulae did not factor in the acceptable ripple level on the output. Adding more capacitance asymptotically reduces ripple and in that sense you are only subject to the law of diminishing returns in terms of cost, weight, volume." Unless in fact you are referring to someone else, all I ever said was that the amount of capacitance required in a PS is inversely proportional to the VDC delivered to the circuit. I did not post any formulae. And yes, one can go crazy with capacitance above and beyond what is really necessary to achieve DC. In part, the excess capacitance makes the PS faster to deliver current if it is suddenly needed. However, that does not apply in Class A circuits or probably for the cartridge.
