Assemble me. Let the celestial music play! The Mechanical Celesta is both a wooden mechanical model and a functional musical instrument. This special musical model is a simpler version of a pianola, and includes elements of a piano, a music box, and a xylophone. There are two modes of playing the instrument: you can use the keys to strike the metal plates, producing musical notes over an octave range, from C to C, or you can "pre-program" the instrument by composing a melody on the player piano drum, then play it by turning the knob!