钢琴音板振动模态的测试和调整

Test and Adjustment of the Vibration Mode of Piano Soundboard

为了研究音板的振动特征,本研究采用激光测振系统对钢琴音板进行20-2000Hz的模态扫描,得到在此频率范围内,单频激励下产生的模态响应,分析了钢琴音板振动能量的频谱与各阶振型特征。参考钢琴声音采集信号的均衡调节参数,用附加质量法对钢琴音板振动进行调整,提出了依据优化音质的均衡频率响应曲线,通过改变附加质量块调整音板振动模式,以改变钢琴的音质。

In order to study the vibration characteristics of the soundboard,laser vibrometer system wasused in this study to extract the modes and energy spectrum of soundboard from20to2000Hz.Goodcorrespondence is observed between the spectrum of the sound signals and the frequencies of thesoundboard vibration modes.With reference to parameters of isostatic adjustment of collected pianosound signal,the author used additional mass method to adjust piano soundboard vibration,and based onthe optimization of sound quality,then put forward the balance frequency response curve.The method ofmass-addition modulation on soundboard vibration modes based on the optimized equilibrium curve offrequency response is proposed as a way to improve the sound quality of piano.