| 摘要 |
<p>[Problem] To provide technology for improving the frequency characteristic by means of an acoustic method so as to enable sounds to be heard with a natural frequency characteristic when a sealed earphone is inserted in a person's ear. [Solution] Two independent sound wave passages are provided in a sound-conducting tube in a sound path that extends from the diaphragm of an electroacoustic converter in the interior of a sealed earphone through the sound-conducting tube and through the ear canal to the ear drum, and the propagation of a specific frequency of sound is controlled by adjusting the length of said passages, thus improving the frequency characteristic of sound passing through this sound path.</p> |
