To provide a loudspeaker that can reproduce sound up to that with an ultrahigh sound frequency even when a magnet with a comparatively small magnetic force is employed.
In this speaker, a voice coil bobbin 21 is mounted on a diaphragm 18, a voice coil 22 is wound on the voice coil bobbin 21 and the voice coil 22 is inserted to a magnetic air gap 16 formed between an inner circumferential face of a plate 15 and an outer circumferential face of a center pole 13a. The inner circumference has an acute angle, this voice coil bobbin 21 is made of a conductive material, the voice coil 22 is adhered and fixed to the voice coil bobbin 21 with a soft adhesive, the voice coil 22 is operated as a drive coil at an ultrahigh sound frequency and the voice coil bobbin 21 acts like a short-circuit coil.
TOKUSHIGE KENJI
SHINOHARA IKUO
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