| 摘要 |
PURPOSE:To make the vertical vibration symmetrical with less distortion by providing two magnetic circuits arranged symmetrically in face in a casing so as to apply vibration to a magnetic circuit with a different resonance frequency. CONSTITUTION:Top plates 14, 24 are fixed to magnets 13, 23, a magnetic gap is formed between the plate 14 and center poles 11, 21 to constitute a magnetic circuit. Moving coils 16, 26 wound on bobbins 15, 25 are placed in the magnetic gap and the bobbins 15, 25 are fixed to the casing 10. The surrounding of each magnetic circuit is supported to the casing 10 by dampers 17, 27. Thus, the reproduced band is changed and selected optionally by giving a difference to the weight of the two magnetic circuits or changing the stiffness of the dampers 17, 27 or changing the resonance frequencies f1, f2. |
