PURPOSE: To improve the high frequency characteristic and to enhance the drive efficiency by connecting a voice coil and an exciting coil so as to allow a signal current of opposite direction to each other to flow to them thereby cancelling the inductive component caused in the voice coil and an exciting coil.

CONSTITUTION: An exciting coil 11 is mounted to an inner wall of a doughnut shaped magnet 2 in the vicinity of a voice coil 7 and the voice coil 7 and the exciting coil 11 are connected in opposite direction, Since a signal current in opposite direction flows to the voice coil 7 and the exciting coil 11, the inductive component caused in both the coils is cancelled and the sound pressure frequency characteristic at a high frequency is improved and since a change in the inductance is small, distortion is reduced, Moreover, since an induced electromotive force in the exciting coil 11 is caused in the voice coil 7, the drive efficiency is improved.