An automatic player musical instrument includes an acoustic piano and an electronic system for selectively producing acoustic tones and electronic tones as regular tones equivalent to the tones to be produced for the keys moved toward the end positions and after-tones equivalent to the tones to be produced for the keys moved toward the rest positions, and a controller of the electronic system makes the acoustic piano and an electronic tone generating system produce the after-tones alone or together with the regular tones depending upon user's instruction so that the users can perform or reproduce music tunes in various renditions such as, for example, tremolo, syncopation and vibrato.