visible sound is a whole of the electromagnetic print
sound_of_heartbeating is audible_sound. audible_sound is not sound. audible_sound is wave_propagation. sound is vibration_of_air. visible_light is non_ionizing_radiation. audible_sound is sound. sound is vibration. synthetic_sound is audible_sound. visible_light is electromagnetic_radiation. visible_light is not electromagnetic_radiation.