melodic harmonic waveforms, sound, movement of air, a good definition, but spoken words, a woman's voice, vibrating air, vibrating electromechanical devices into electrical impulses transmitted wirelessly and received, electrical impulses driving membranes that vibrate air, that vibrates a membrane in my ear transformed to more neuron activity and then neural storm and flashes of light and endorphins are released. amazing how the movement of air molecules, a whole bunch moving in waves, at the smallest scale, biggest effect, sweetest sound.