Positional control of the keys (not the hammers) is possible but the solenoids get very hot. Strike velocity is not proportional, I will have to add some filtering to ensure that loud passages don't break a hammershank.
As for the tonal effects, you can't really manipulate a piano hammer like that through the action, and this mechanism still uses the normal action the way it is intended, only it strikes from below the pivot rather than above, so at the back of the key. The whole function of the piano action is to give a uniform response to uniform input so the hammer can only describe a particular arc with a speed relative to the force with which the key is struck. You can't 'freeze' the hammer at the top of that arc, it will just fall back down until it gets caught by the back-checks.
What you can do and what would be impossible with just one pianist and just your fingers is to strike key combinations that would be otherwise impossible. For instance to make a chord that uses more than the normal number of fingers or that would require extreme contortions or more than two hands.
As for the tonal effects, you can't really manipulate a piano hammer like that through the action, and this mechanism still uses the normal action the way it is intended, only it strikes from below the pivot rather than above, so at the back of the key. The whole function of the piano action is to give a uniform response to uniform input so the hammer can only describe a particular arc with a speed relative to the force with which the key is struck. You can't 'freeze' the hammer at the top of that arc, it will just fall back down until it gets caught by the back-checks.
What you can do and what would be impossible with just one pianist and just your fingers is to strike key combinations that would be otherwise impossible. For instance to make a chord that uses more than the normal number of fingers or that would require extreme contortions or more than two hands.