Abstract: Keyboards, input devices, and related systems include key mechanisms with keycaps and actuators that provide adjustable feedback in response to user input. The actuators are controllable to provide variable tactile force or audible feedback that is dependent upon the user input. Encoders are able to transduce a location or relative position of a keycap as it is being pressed over time, and a signal is provided to actuators to cause them to provide feedback corresponding to the position of the keycap as it moves. The feedback can change the feel or sound of the keycap based on the keycap positions, time of operation, velocity, user identity, and other factors. Thus, the feel or sound of a keyboard or related input device can be adjusted electronically for efficient testing and increased user customization and feedback modes.