| 摘要 |
PROBLEM TO BE SOLVED: To provide a sound structure which surely prevents the occurrence of a sound obstacle in acoustic space even in the case when a sound wave in a high frequency band is generated in the space.SOLUTION: Cavities 22-i (i=1-6) of a sound structure 1 communicate with outer space through openings 21-i (i=1-6) of a board 18. Sound absorbing materials 30-m (m=1-7) in which the absolute value |ζ| of a specific acoustic impedance ratio ζ is equal to or less than 1 are attached in the area excluding the openings 21-i (i=1-6) and the vicinity of the openings 21-i (i=1-6) on a reflection surface ref on the opposite side of the cavities 22-i (i=1-6) of the board 18. |
