| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an acoustic characteristics measuring device capable of measuring acoustic characteristics stably up to a high frequency range. <P>SOLUTION: An acoustic characteristics measuring device has a sound source 12 provided at one end of an acoustic pipe 11 housing a test sample 13 to be measured, excites a plane wave in the acoustic pipe 11 with the sound source 12, measures a complex sound pressure transfer function between two positional points in the longitudinal direction between the sound source 12 and the test sample 13 with measuring-aid microphones 18-1, 18-2, and 18, and can calculate acoustic characteristics from this complex sound pressure transfer function, where the bore ϕ2 of the acoustic pipe 11 is smaller than or equal to 14 mm, and the diameter D2 of the openings of the fitting parts of the measuring-aid microphones 18-1 and 18-2 to the acoustic pipe 11 is smaller than or equal to 1/3 of the bore ϕ2 of the acoustic pipe 11. <P>COPYRIGHT: (C)2013,JPO&INPIT |
