PURPOSE: To realize a flat panel speaker which is extremely and light in the entire form and thus to enhance both the electroacoustic conversion efficiency and the frequency property by exciting the diaphragm with the magnetic flux generated from several coils and the signal current flowing to several electrode bars.

CONSTITUTION: The parallel electrode consisting of parallel electrode bars 31a and 31b are provided on the signal or both surfaces of diaphragm 30, and the magnetic flux is generated via coils 40a, 40b∼40n and in the direction parallel to diaphragm 30 is orthogonal to electrodes 31a and 31b. Thus diaphragm 30 is vibrated by the magnetic flux generated from coils 40a∼40n plus the signal current flowing to electrode bars 31a and 31b. In such way, a flat panel speaker is obtained with an extremely thin and light form as a whole, thus enhancing both the electroacoustic conversion dfficiency and the frequency property.