"Don Pablo" Melodica with case. Also known as the "pianica", "blow-organ", "key harmonica", or "melodyhorn". The melodica is a free-reed instrument similar to the pump organ and harmonica. It has a musical keyboard on top, and is played by blowing through a mouthpiece that fits into a hole in the side of the instrument. The melodica has experienced a surge in popularity in Puerto Rico an other Latin American countries.