Acoustics Research Group, Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom.
J Acoust Soc Am. 2012 Jan;131(1):872-7. doi: 10.1121/1.3651232.
This paper presents an experimental study of the effects of prestresses on the vibration behavior of string instruments. These prestresses are created by gluing ribs (crowning) and tensioning string (downbearing). The effects of these prestresses were previously studied numerically for a piano soundboard by Mamou-Mani et al. [J. Acoust. Soc. Am. 123, 2401-2406 (2008)] and analytically for simplified models by Mamou-Mani et al. [Acta Acust. Unit. Acust. 95, 915-926 (2009)]. In the present study, a specified test bench is designed, including a simplified soundboard (a rectangular plate), a bridge, and a single string. The plate is subjected to in-plane and transverse loads. Vibrational eigenmodes are identified using nearfield acoustical holography (NAH) measurement. The evolution of eigenfrequencies with these specific prestresses is studied. The results show the effectiveness of NAH for this purpose and a very good qualitative concordance with previous numerical and analytical calculus.
本文对弦乐器振动行为中预应力的影响进行了实验研究。这些预应力是通过粘贴肋骨（起拱）和拉紧琴弦（下压力）产生的。Mamou-Mani 等人曾通过数值方法研究过钢琴音板的这些预应力的影响[J. Acoust. Soc. Am. 123, 2401-2406 (2008)]，并通过 Mamou-Mani 等人的简化模型进行了分析[Acta Acust. Unit. Acust. 95, 915-926 (2009)]。在本研究中，设计了一个特定的测试台，包括简化的音板（矩形板）、桥和单根琴弦。板承受面内和横向载荷。通过近场声学全息（NAH）测量识别振动本征模态。研究了本征频率随这些特定预应力的变化。结果表明，NAH 非常适合于这种用途，并且与以前的数值和分析计算具有很好的定性一致性。
