Changes in wave propagation in a guitar top plate due to the fan bracing and the bridge

Wave propagation on a guitar top plate was explored using transient analysis. The goal of using time domain, instead of frequency domain as it is commonly reported, was to achieve a more simple approach about the influence of the fan bracing and the bridge. For this purpose, the elastic properties of a real top plate were measured through simple experiments, in order to build the respective finite element model. The model exhibited good agreement with experimental behaviors of the literature. In the same top plate, the propagation of two kinds of waves was simulated; one analysis was done using one wave of high harmonic content, and another applying a wave with low harmonic content. Results showed, to naked eye, that the velocity of propagation over the top plate clearly changed due to their interactions with the attached structures. Such change was particularly noticeable for waves of short wavelength, in other words, for high frequencies. Then, it is evident that for guitars, designs of fan bracing and bridge are crucial, mainly, in treble sounds radiated by the instruments. (C) 2013 Published by Elsevier Espana, S.L.U. on behalf of CIMNE (Universitat Politecnica de Catalunya).