loudspeaker Device for converting changing electric currents into sound. The most common type has a moving coil attached to a stiff paper cone suspended in a strong magnetic field. By electromagnetic induction, the changing currents in the coil cause the cone to vibrate, thus creating sound waves. Many modern loudspeakers give faithful sound reproduction between 80 and 20,000 hertz. See also microphone; sound recording

loud·speak·er / ˈloudˌspēkər/ • n. an apparatus that converts electrical impulses into sound, typically as part of a public address system or stereo equipment.