| 摘要 |
PURPOSE:To improve sound absorbing efficiency by decreasing the cross-sectional area of an acoustic box toward the inside of the acoustic box from a speaker mounting part. CONSTITUTION:A speaker 1 is mounted on a front buffle board 2, the cross-sectional area of the acoustic box is decreased toward a backward direction so as to narrow a sound path 5 and a port 3 and an air flow resistance board 4 are provided to the rear end part. Since the sound path 5 is narrowed toward the backward direction, both ends of wave front touch the inner face at one point in the sound wave irradiated from the back side of the speaker and the wave is restricted for propagation so that the wave front is deformed into a bow. The compressional wave of sound is cancelled together and the sound absorbing effect is improved. |
