Comparison of the vibroacoustical characteristics of different pianos

TL;DR

This paper compares various vibroacoustical models of piano soundboards, focusing on bridge-plate coupling, and validates model predictions against experimental data across different piano types.

Contribution

It introduces several models for bridge-plate coupling, demonstrating their accuracy in predicting modal density and impedance without parameter tuning.

Findings

Sub-structure model fits experimental data precisely

Elastic wood parameters significantly influence vibroacoustical characteristics

Model predictions vary with piano size and type

Abstract

On the basis of a recently proposed vibro-acoustical model of the piano soundboard (X. Boutillon and K. Ege, Vibroacoustics of the piano soundboard: reduced models, mobility synthesis, and acoustical radiation regime. \emph{submitted to the Journal of Sound and Vibration}, 2011.), we present several models for the coupling between the bridge and the ribbed plate of the soundboard. The models predict the modal density and the characteristic impedance at the bridge as a function of the frequency. Without parameter adjustment, the sub-structure model turns out to fit the experimental data with an excellent precision. The influence of the elastic parameters of wood is discussed. The model predictions are compared for pianos of different sizes and types.