Traveling wave control of stringed musical instruments
Liam Donovan, Andrew McPherson · The Journal of the Acoustical Society of America · 2017
Traveling wave control is a technique in which the energy propagating around a structure in the form of waves can be manipulated directly in order to change the overall dynamic behaviour of the structure. In this research, traveling wave control is applied to a musical instrument string with a view to affecting the timbre of the sounds produced by the string when vibrating. A highly linear custom optical sensor is built which is capable of detecting a wave traveling on a string in a single direction, and a piezo stack actuator is situated under the termination point of the string allowing the reflection of the wave to be manipulated directly. Various controllers are analyzed theoretically in terms of their performance, stability, and musical usefulness. They are then implemented and evaluated in terms of their relevance to the design of new musical instruments.