The cosmic piano is a set of electrically charged particle detectors, based on plastic scintillator material, designed to detect secondary cosmic ray particles, mainly muons and electrons. Besides the typical use of those apparatus to detect the arrival of air shower cosmic ray particles, we converted the electric signals generated when those particles impact the cosmic piano detectors into beep sounds and spotlights produced by each one of the detectors. Then, light flashes and random musical notes surround the environment when secondary cosmic rays pass through the cosmic piano detectors. In this enjoyable way, we show to the general public, from scratch to real working experiments, the functionality of elementary particle detectors and the passing of cosmic rays through the Earth's surface.