| 摘要 |
A dynamic-type headphone in which a diaphragm 5 has a bobbin 7 for a voice coil 8 located within a magnetic circuit 3, 2, 1, 4 and is formed of one sheet made of polyethylene terephthalate resinous material and in which, if the diameter of a vibrating portion of the sheet is taken as ??? and the thickness thereof is taken as t then t DIVIDED ???=4x10<-4> to 5x10<4>. <IMAGE> |
