PURPOSE: To achieve a speaker with good sound quality with full drive, by prividing a radiator in which a voice coil is provided at the surface of insulator, in a flat coil forming a magnetic field through the supply of DC current.

CONSTITUTION: A conductor voice coil 2 is sticked in pattern shape on the surface of an insulator 1 to form a radiator. A fixed parallel conductor 3 being a flat coil is provided to the outside of the radiator. With the constitution, driving force can be applied to a braod radiator entirely by flowing an audio current to (a), (b) and a DC for magnetic field to (c) and (d), allowing to achieve a speaker emphasized with audio quality.