樂器物理模型之新趨勢

Abstract

本論文介紹樂器的物理模型，及其在商業上以及學術上的發展趨勢，並強調模擬樂器演奏法的必要性。物理模型樂器在學院中引導商業合成器之實現，因此國立交通大學在音樂科技的研究上，有很大的機會可參與其中。在交大的學院資源性與接近園區工業的便利性上均可促進相關此類模擬樂器演算法的發展。這些樂器例如琵琶與古琴均可成為此研究之出發點，因為撥絃樂器的通用演算法已經有所發展，而某些西方與東方樂器的模擬已經成功地實現，吾人可指出這些樂器包括了吉他、曼陀林琴，以及印度西塔琴。因此藉由交大的音樂科技研究團隊在物理模型技術上的學習，可提出其方法並實現此目標。同時吾人亦指出研究控制上述樂器參數之人機介面的重要性。這些樂器都是撥絃類樂器，然而它們並不具有相同的演奏法。因此這些樂器的特殊化控制器亦需要設計。本論文包含了「古典」合成法則與物理模型合成法則之比較，聲響樂器之物理模型技術的綜整，以及控制器參數介面與一些利用Karplus-Strong演算法來實現撥絃類樂器之實驗。

This thesis introduces the topic of the physical modeling for musical instruments and its current trends in the commercial and academic world, emphasizing on the necessity of the emulation of musical instruments’ performance articulation. The physical modeling instrument topic has lead to the commercial implementation. Therefore a great opportunity to participate can be seen for the Music Technology Research at National Chiao Tung University. The academic resources and the proximity with the technology industry of Taiwan R.O.C may facilitate the development of an algorithm or set of algorithms to emulate musical instruments. Instruments like the Pipa (琵琶) and the Guqin (古琴) could be a start point for a research because generic algorithms for plucked instruments have been developed. Simulations of some western and eastern instruments have been successfully implemented; we can mention the guitar, the mandolin and the sitar. Therefore, by learning the techniques of physical modeling the Music Technology Research Team of National Chiao Tung University can propose a methodology and accomplish this goal. On the other side, we mention the importance of a research on interfaces to control the parameters of instruments. In the case of Pipa and Guqin both of them are plucked instruments however they do not share the same performing articulations. Therefore, specialized controllers for these instruments should be designed. This thesis contains, comparisons on “Classic” synthesis and physical modeling synthesis, a summary of physical modeling techniques of acoustic instruments, interface and parameter controllers trends and experimentation with the Karplus-Strong Algorithm for plucked string instruments.