| 摘要 |
PURPOSE:To fit closely a speaker cabinet at a wall and to prevent the reduction of an efficiency of a low voice by providing an open hole and a cover composed so as to surround the open hole, at a part of the cabinet, and positioning the open hole part of a cover except the surface to extend the side surface of the speaker cabinet. CONSTITUTION:The rear pressure of the speaker 1 transmits through the compliance of a cabinet 2 to the first open hole 3, passes through the port surrounded with a cover 4 and a cabinet 2 and radiated from the second open hole 5 to the external part of the speaker. At such a time, judging from a sound pressure frequency characteristic in an audition room, even when a speaker cabinet is fitted closely to a wall surface 6, the second open hole is hardly closed, and therefore, the speaker with a high efficiency for the sound pressure only due to the radiation from the port as shown by (a) in the figure can be constituted. |
