| 摘要 |
PURPOSE:To reduce the distortion of output of a speaker by a method wherein grooves are provided along the face being adjacent to the gap between facing magnetic poles, and coils to make a current to flow therein in the direction to negate line of magnetic field generated by a moving coil are buried in the grooves. CONSTITUTION:The grooves 13 are provided along the face of the central magnetic pole 1 being adjacent to the gap 3, the current is made to flow in the compensating coils 11 being put in the grooves 13 in the direction as to generate opposite directional magnetic field to the direction of crossing magnetic field 10 to be generated when a current flow in the moving coil 8 to suppress generation of crossing magnetic field 10. Accordingly distortion of output to be generated by a disturbance owing to crossing magnetic field can be reduced. |
