| 摘要 |
<p>Provided are a first speaker array which has plural first speaker units arranged in a first surface and outputs a first sound that is directed to a particular first directivity direction and is such that an angle of the first directivity direction with respect to an arrangement direction of the plural first speaker units can be adjusted; and a second speaker array which has plural second speaker units arranged in a second surface that is different from the first surface and outputs a second sound that is directed to a particular second directivity direction and is such that an angle of the second directivity direction with respect to an arrangement direction of the plural second speaker units can be adjusted. Where the second speaker array is installed together with the first speaker array in a room having a ceiling as a sound reflection surface, the second speaker array is installed in such a manner that the normal to the second surface is in such a direction that the second sound emitted from the second speaker array reaches, only indirectly, through reflection or diffraction, a sound receiving point that is located in a direction of the normal to the first surface and set as a position for listening to the first sound or that the second sound reaches the sound receiving point with such a sound volume that a ratio of a sound pressure of the second sound that reaches the sound receiving point after being reflected by the ceiling to that of the second sound that reaches the sound receiving point directly is larger than or equal to a prescribed value.</p> |
