| 摘要 |
PROBLEM TO BE SOLVED: To provide a speaker device which prevents sound quality degradation caused by resonance and capacity decrease by filling of a sound absorber, and costs down on costs through control of the amount of sound absorber usage. SOLUTION: An open edge C is provided at the bottom edge of a cylinder-shaped cabinet 12, and a speaker unit 16 is upwardly mounted on the top edge of the cabinet 12 through a gel-type ring. Sound waves are transmitted through the cabinet 12 backward of the speaker unit 16. Column-shaped or doughnut-shaped sound absorbers D4, D3, D2 and D1 are inserted into the cabinet 12 at positions in the cabinet corresponding to the anti-node of a one-quarter wavelength sound pressure amplitude that resonates at a natural frequency of the cabinet 12, the anti-node of a three-quarter wavelength sound pressure amplitude, and the anti-node of the sound pressure amplitude of a five-quarter wavelength standing wave respectively, from the open edge C of the cabinet 12. Thereby, the occurrence of a standing wave that resonates to the natural frequency of the cabinet 12 is controlled, and prevents sound quality degradation due to resonance. COPYRIGHT: (C)2009,JPO&INPIT
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