| 摘要 |
A technology which improves frequency characteristics by an acoustic method so that, when a sound-isolating earphone is attached to a human ear, the sound is heard with natural frequency characteristics is provided. In a sound path from a diaphragm of an electro-acoustic transducer inside a sound-isolating earphone to the eardrum passing through a cylindrical sound leading pipe via the external auditory canal, two independent paths for sound waves are provided in the sound leading pipe, and transfer of the sound with a specific frequency is suppressed by adjusting a difference in length of the paths, whereby the frequency characteristics of the sound passing through this sound path are improved. |
