鐵琴樂器之聲音特性分析與驗證

Sound Characteristic Analysis and Verification of Metallophone Instrument

王栢村(Bor-Tsuen Wang) ； 簡孝名(Xiao-Ming Jian)

《機械技師學刊》 3卷2期 (2010/06) Pp. 1-7

https://doi.org/10.6208/JPME-2010-02-01

摘要

本文將針對鐵琴樂器所包含之12片不同音階鐵琴片，對敲擊後之敲擊音進行聲音特性之探討，並對鐵琴片進行有無加速度計於自由與實際邊界下之模型驗證，藉此建構出參數化之鐵琴片有限元素模型，以進行不同音階尺寸之鐵琴片分析。首先，建構鐵琴片的有限元素模型，並進行鐵琴片於自由邊界與實際邊界下之實驗模態分析，量測不同邊界下鐵琴片之模態參數，將分析與實驗所得到的模態參數進行比較修正後，可獲得等效於自由邊界與實際邊界下鐵琴片的有限元素模型。最後，運用所得到的鐵琴片有限元素模型進行不同音階之模擬預測。從結果得知，經驗證後之鐵琴片有限元素模型可實際用來模擬預測不同音階鐵琴片之模態特性。未來可利用此鐵琴片之有限元素模型快速的進行鐵琴片之理論分析，以獲得理論的模態參數，這將有助於往後對於鐵琴片設計製作。

關鍵字

鐵琴片 ； 實際邊界 ； 模型驗證 ； 有限元素模型 ； 實驗模態分析

並列摘要

This work aims to discuss the percussion sound of the metallophone instrument that contains a dozen of metallophone bars producing different notes. The modal parameters of a metallophone bar is experimentally obtained for with and without the accelerometer mass effect in both free and practical boundaries. The finite element analysis (FEA) is also adopted to construct the parametric FE model for analyzing all of the metallphone bars with different sizes. First, the FE models for both free and real boundaries are constructed and performed modal analysis. The corresponding experimental modal analysis (EMA) on both boundaries are, respectively, performed. The modal parameters obtained from FEA and EMA can then be compared to update and validate the FE models in both boundaries. Finally, the verified FE model is adopted to predict the modal properties of the metallophone bars for different notes. Results show that the modal sound response is well calibrated with the experiments. The developed parametric FE model for the metallophone in real boundary can be useful for the design and manufacturing of the metallophone bars.

並列關鍵字

metallophone ； real boundary ； finite element analysis FEA ； experimental modal analysis EMA