A transducer which converts variations of electrical current into sound vibrations. The principle of the loudspeaker is the exact reverse of that of the microphone. It is driven by an amplifier (which may be housed in a separate cabinet or combined with the loudspeaker in a single ‘combination unit’), and is the exact reverse of the microphone. The loudspeaker is an essential component of every electro-musical system. A loudspeaker cabinet for professional or domestic use normally contains at least a substantial mid-range unit and a ‘tweeter’ for higher frequencies; a larger cabinet or a separate bass loudspeaker will also incorporate a low-frequency ‘woofer’. A loudspeaker installation for a large space, temporary or permanent, is normally known as a PA (‘public address’) system.
See also Electric guitar and Electronic instruments, §I, 5(ii).
G.A. Briggs: Loudspeakers (Bradford, 1948, 5/1958)
G. Slot: From Microphone to Ear: Modern Sound-Recording and Reproduction Technique (Eindhoven, 1956, 2/1959)
J. Borwick, ed.: Loudspeaker and Headphone Handbook (Oxford, 1988, 2/1994)
HUGH DAVIES