| 摘要 |
PURPOSE:To prevent the howling of low range from being generated by interposing an insulator between a speaker box and a floor such that the resonant frequency of the speaker box in preset two directions takes a preset range. CONSTITUTION:There are interposed between a speaker box 1, which is operative to generate main vibrations substantially in a horizontal direction, and a floor 5 a plurality of insulators which are equipped with a rectangular or cylindrical rubber element having a low hardness, a similar rubber element formed with grooves 4a, a leaf spring equipped with an upright elastic member, and elastic projecting members 4c mounted on an elastic support 4b. By these insulators 4, the resonant frequency of the speaker in the main direction can be adjusted to 1 to 10 Hz, whereas the vertical resonant frequency in the vertical direction can be adjusted to a level higher than 20 KHz to that the howling of low range can be prevented. |
