Seeing the sound of castanets: Acoustic resonances between shells captured by high-speed optical visualization with 1-mm resolution

Kenji Ishikawa*, Kohei Yatabe, Yasuhiro Oikawa

*この研究の対応する著者

研究成果: Article査読

抄録

Sound fields radiated from the castanet, a Spanish percussive instrument comprising two shells, were optically visualized. A measurement system, which used parallel phase-shifting interferometry and a high-speed polarization camera, enabled the capture of instantaneous sound fields around the castanets, while the castanets were played, with the spatial resolution of 1.1 mm and frame rate of 100 000 fps. By carefully aligning the tilt of the castanets, the sound fields within the 1-mm gaps between both the shells were captured. From the visualization results, two acoustic resonances between the shells were identified. The first mode appeared between 1000 and 2000 Hz and exhibited a frequency chirp of several hundred hertz for several milliseconds after the impact. This can be explained by the Helmholtz resonance with a time-varying resonator shape, which is caused by the movement of the shells after impact. The second mode showed a resonance pattern with a single nodal diameter at the center of the shells, i.e., the standing wave mode caused by the interior volume. These physical phenomena involved in the sound radiation were identified owing to the unique features of the optical imaging method, such as contactless nature and millimeter-resolution imaging of instantaneous pressure fields.

本文言語English
ページ(範囲)3171-3180
ページ数10
ジャーナルJournal of the Acoustical Society of America
148
5
DOI
出版ステータスPublished - 2020 11 1

ASJC Scopus subject areas

  • 人文科学(その他)
  • 音響学および超音波学

フィンガープリント

「Seeing the sound of castanets: Acoustic resonances between shells captured by high-speed optical visualization with 1-mm resolution」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル