• The Journal of the Acoustical Society of Korea
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• v.26 no.1
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• pp.1-7
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• 2007

This paper presents a study on acoustic characteristics and sound generation mechanism of Cryptotympana atratas' songs which cause noise problems in summer days. The waveforms & FFT of Cryptotympana atratas' songs in nature were analyzed, and the actions of tymbals were visualized by the high speed camera. In order to know resonance frequency of the abdominal cavity of male Cryptotympana atrata, the sine sweep test was done. It was observed from the experimental results that Cryptotympana atrata's two tymbals act asymmetrically with respect to time & shape, and make a variety of frequencies every time it vibrates. It was also shown that Cryptotympana atratas' have a structure that cause resonances sounds only in a $7{\sim}7.5 kHz$ bandwidth.