| 摘要 |
PROBLEM TO BE SOLVED: To simultaneously test sound absorbing performance and sound insulating performance while being the simple constitution, and reduce the cost. SOLUTION: A loudspeaker 20 for outputting a sound wave in a test tube 10 is provided on the other end side of the test tube 10 for arranging a test piece 21 of a sound absorbing material A on one end side and selectively arranging a test piece 22 of a sound insulating material B in an intermediate part, a freely attachable microphone 30 is arranged for measuring sound pressure of an incident sound wave incident on the test piece 22 of the sound insulating material B by being outputted from the loudspeaker 20 in the test tube 10, a microphone 31 is arranged for measuring either one of a transmitted sound wave transmitted through the test piece 22 and sound pressure of an incident sound wave directly incident on the test piece 21 of the sound absorbing material A from the loudspeaker 20 and sound pressure of a reflected sound wave reflected from the test piece 21, and a computer 40 is arranged for arithmetically operating at least either one of the sound absorbing performance and the sound insulating performance of the test pieces 21 and 22 on the basis of the detected sound pressure.
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