Acoustics of the banjo: theoretical and numerical modelling

A previous paper [Woodhouse et al., Acta Acustica 5, 15 (2021) https://doi.org/10.1051/aacus/2021009 ] showed acoustical measurements of an American 5-string banjo alongside similar on a guitar, revealing strong contrast in bridge admittance. Theoretical and numerical modelling is now presented to probe the physics behind this contrast. Without strings, membrane has rising trend admittance associated with its modal density, it distinctive pattern sound radiation because ideal no critical frequency. When strings are added banjo, three formants shape amplitude envelope One local effects mass stiffness near bridge, sensitive break angle over bridge. The other two dynamical behaviour analogous “bridge hill” violin.