楽器響板用木材の音響特性に及ぼすニス塗装の影響

• 小野,晃明

  Department of Physics, Faculty of Engineering, Gifu University

書誌事項

タイトル別名

• Effects of varnishing on acoustical characteristics of wood used for musical instrument soundboards

抄録

Tapping sounds were measured for the varnished boards and the uncoated ones of Sitka spruce wood used for musical instrument soundboards, and the acoustical effect of varnishing was investigated from their sound power spectra. The Young's modulus and the internal friction were measured for these boards, and the equations for the case of a coated board were derived theoretically. From these experiments and theories, the important mechanisms were clarified. With varnishing, the sound power level decreased at low-frequencies (< 300Hz), and it increased or decreased at high-frequencies (> 3kHz) and overall. This difference in frequency characteristic variations was due to the difference in variations of Young's modulus(E_R) and internal friction (Q^<-1>_R) in the direction, R, perpendicular to the grain. The level drop at low-frequencies was due to the shifting upwards of the lowest mode frequency with increasing E_R. For wood having a low E_R value the power level increased at frequencies above about 300Hz because of the larger increase of E_R, whereas for wood having a high E_R value it decreased at high-frequencies because of the larger increase of Q^<-1>_R. The varnishing is beneficial acoustically in the former but harmful in the latter regardless of varnish thickness.

収録刊行物

• Journal of the Acoustical Society of Japan ?

  Journal of the Acoustical Society of Japan ? 14 (6), 397-407,

  Japan Acoustical Society of Japan

キーワード

• Varnishing
• Tapping sound
• Sound power spectrum
• Young's modulus
• Internal friction

詳細情報

• CRID: 1544231895017508224
• NII論文ID: 110003106070
• NII書誌ID: AA00256597
• Web Site: http://dl.ndl.go.jp/info:ndljp/pid/10571504
• 本文言語コード: en
• データソース種別:
  • NDL-Digital
  • CiNii Articles