| 摘要 |
PURPOSE:To suppress the resonance frequency component due to a sound guide path selectively by providing a resonator sound absorbing material absorbing the resonance frequency component of the sound guide path so as to act on the sound guide path. CONSTITUTION:Resonator sound absorbing bodies 51, 52 are provided respectively to upper and lower outer sides of an expanded tube part 41 of a sound guide path 4 to absorb the resonance. The resonator sound absorbing bodies 51, 52 have ports 61, 62 opened toward the middle of the sound guide. 4, especially toward the border between the expanded tube part 41 and the parallel tube part 42 to form a Helmhortz resonator. The resonance frequency of the upper resonator 51 is slightly higher than the 0-th order resonance frequency of the sound guide path 4, while the resonance frequency of the lower resonator 52 is slightly lower than the resonance frequency. Thus, the component of the resonance frequency from the sound guide path is absorbed selectively. Then the accurate reproducing sound is obtained with high efficiency. |
