| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a speaker system adopting a distributed loudspeaking system suitable for sound image localization. <P>SOLUTION: A plurality of downward speakers 21 are located on a ceiling 5 above a sound receiving face Ph in a distributed way, and a diaphragm 22 of each speaker 21 is formed to be a hyperbolic paraboloid shape. An outer diameter W of a diaphragm 22 is sized to easily obtain a required sound pressure level at a sound receiving face Ph depending on a distance from the sound receiving face Ph (a ceiling height H-a sound receiving face height h), and a ratio of a diameter B of a voice coil coupled to an inner end of the diaphragm 22 along the shape of the diaphragm to the outer diameter W is decided such that the directivity characteristic is flat for a low and medium sound region and gradually slows down for a high sound region. Preferably, the diameter B of the voice coil is selected to be 28 to 69% of the outer diameter W of the diaphragm. The diaphragm 22 is desirably made of material having low density and high Young's modulus. More preferably, a horn 25 with an aperture angle in response to the distance between the sound receiving face Ph and the ceiling 5 is mounted on each speaker 21 and each diaphragm 22 is used for a horn driver. <P>COPYRIGHT: (C)2004,JPO |
