| 摘要 |
PROBLEM TO BE SOLVED: To provide a passive noise isolation attachment of low price for earphone not having an active electronic circuit, and in which both isolation performance of environmental noise, and sound passing performance of reproduction sound are stable and satisfying a certain level.SOLUTION: An absorber for ear plug is provided with a first non-through hole, and a second non-through hole is provided in the bottom of the hole, thus preventing the core piece of the absorber from being absorbed to a hollow portion in the vicinity of the auditory canal. A cutout is provided in the cut area of the core piece attached to the first hole in the auditory canal side thereof. Inlet of the auditory canal and the cutout of the core piece can face each other, by slight adjustment of the attachment state of the earphone, and local absorption of the absorber into the hollow portion is prevented at that part. |
