A dynamic phono pickup, MM or MC, puts out a voltage that is proportional to the RATE of stylus movement. A piezioelectric phono pickup (and there were some that were not cheap junk) puts out a voltage that is proportional to the DISPLACEMENT (distance of movement) of the stylus. And yet, both can play the same LP groove, and sound more or less the same. This has always puzzled me.
Now, I wonder what kind of signal the laser pickup produces...rate or displacement, or something else. Clearly there is room for a distinctly different sound from the same groove.