Make a rhodes piano that doesn't decay. Can start from a strike or from the excitation. The examples sound like an ebow made for the rhodes.
Rhodes has enharmonic overtones, especially on the strike. The pickup gets mostly integer multiples of the fundamental, especially even partials.
the actuator is an electromechanical coil driven by a sinetone generator of the fundamental. The pickup also grabs the actuator, so they remove the phase inverse of it past the pickup. They can also use feedback to drive the tine. This causes out of control feedback, so they sense the output just of the actuator and subtract that out, leaving just the tine, thus getting increasingly rube goldberg.
there are pros and cons of each approach. They measure after touch for control using a pressure sensor below each key. Appropriately, all the dignal processing is analog