A method of making musical sounds from a musical instrument may include amplifying musical sounds from vibrations of a vibrating element when a musical instrument is played, sensing forces between the musical instrument and the vibrating element and altering the forces applied to the vibrating element in response to the sensed forces to emulate musical sounds produced by a musical instrument having different musical characteristics, for example, to emulate an acoustic guitar. Piezoelectric material or magnetic material may be used to apply forces along one or more than one axis of vibration and may be controlled by a replaceable element and/or in response to user adjustments. The applied forces may be adjusted to control relative phase between the sensed and applied forces to avoid unwanted musical effects, such as unwanted sustained oscillation, in response to a fundamental period of the vibrations or random number generation to change the vibration waveform.