Wind chimes

Wind chimes produce clear, pure tones when struck by a mallet or suspended clapper. A wind chime usually consists of a set of individual alloy rods, tuned by length to a series of intervals considered pleasant. These are suspended from a devised frame in such a way that a centrally suspended clapper can reach and impact all the rods. When the wind blows, the clapper is set in motion and randomly strikes one or more …

…the inner ear (cochlea). Hair cells along the basilar membrane (which runs the length of the cochlea) perceive the disturbances and interpret them as auditory signals to be transmitted to the nervous system. With pure tones such as those created by a wind chime, certain groups of hair cells are agitated more than others-- and the position of that group along the basilar membrane can be directly correlated to the relative pitch of the tone.