Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.
J Acoust Soc Am. 2010 Jul;128(1):EL8-13. doi: 10.1121/1.3425742.
The Balinese gamelan gong ageng wadon produces distinct acoustic beating (called ombak) when struck. This phenomenon is explored using both acoustical and vibrometry measurements. The measurements have revealed the beating has two sources. First, there are four closely spaced modes that, given their asymmetric vibration patterns, might have been deliberately hammered into the response of the gong. Second, and more importantly, a nonlinear structural response of the gong causes the fundamental axisymmetric mode to produce harmonics. The second harmonic of the fundamental mode interacts with the second axisymmetric mode with relative amplitudes such that strong beating is produced.
巴厘岛佳美兰 Gong Ageng Wadon 在敲击时会产生独特的声学拍频（称为 ombak）。本研究使用声学和振动测量法对这一现象进行了探索。测量结果显示，拍频有两个来源。首先，有四个紧密间隔的模式，由于其非对称的振动模式，可能是被有意地敲击到了锣的响应中。其次，也是更重要的是，锣的非线性结构响应导致基轴对称模式产生谐波。基频的二次谐波与第二个轴对称模式以相对幅度相互作用，从而产生强烈的拍频。
