| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technique for improving frequency characteristics with an acoustic method thereby to allow a user to listen to sound with natural frequency characteristics when a seal type earphone is mounted on a human ear. <P>SOLUTION: A seal type earphone includes two or more electroacoustic transducers. Independently generated sonic waves pass through independent sound guide ducts and are mixed before the entrance of an external auditory canal. Then, the sonic waves with a wavelength twice as long as a route difference between the two sound guide ducts are attenuated. Consequently, sound quality is improved to be more listener-friendly by suppressing the sonic waves around 6 khz to be characteristically strongly transmitted in the seal type earphone. <P>COPYRIGHT: (C)2013,JPO&INPIT |
