Examination of polarization coupling in a plucked musical instrument string via experiments and simulations

Acta Acustica

Brauchler Alexander¹  Eberhard Peter¹  Ziegler Pascal¹ 

[1] Institute of Engineering and Computational Mechanics, University Stuttgart;

关键词: guitar string vibration;    musical instruments;    realistic plucking;    ldv measurement;    experimental study;    numerical study;   

DOI  :  10.1051/aacus/2020008

来源: DOAJ

【 摘 要 】

In this article, the transient motion of a realistically plucked guitar string is studied experimentally and numerically in both transversal polarizations. The frequency dependent damping and suitable initial conditions are identified in the experiment and used in a simulation. For this reason an experimental set-up consisting of a string, an excitation mechanism and two laser Doppler vibrometers is developed. The excitation mechanism performs a realistic and reproducible plucking motion with a plectrum. Two laser Doppler vibrometers are used to measure the string oscillation transversally in two polarizations. The experimental set-up makes it possible to measure the string’s motion under reproducible conditions and, hence, at different positions for the same oscillation. This capability renders the identification of suitable initial conditions, i.e., initial displacement and velocity as well as the pre-tension, for a string model possible. Furthermore, a finite element model for the string is developed that takes into account the oscillation in both transversal planes of polarization and the coupling between them. Finally, the model results are in good agreement with the measurements. With help of the numerical model it can be vividly shown that the coupling between the polarizations of the oscillation is due to a torsional movement of the string on the saddle.

【 授权许可】

Unknown