Acoustical Survey and Finite Element Analyses of Late Baroque Mandolin

Abstract

Abstract Replicating ancient musical instruments is a method to protect fragile originals from extensive playing. In the case of stringed instruments, replicas are generally realized by luthiers using identical wood species and geometry, according to dimensional surveys. Although this procedure yields a highly similar visual aspect, the intrinsic variability of wood properties does not ensure an identical sound. Therefore, acoustic surveys are a fundamental step in reproducing the sounds of original instruments. In this work, we report the acoustical survey of a late baroque mandolin preserved at Museo degli Strumenti Musicali del Castello Sforzesco di Milano. The survey was conducted using portable equipment and included measurements of the radiated sound spectrum, admittance, monopole mobility, and mode shape assignment. Finite Element Analyses (FEA) enabled the assignment of mode shapes and quantification of the effect of a crack on the structural integrity and acoustics of the instrument. This study has laid the foundation for the creation of a replica that, beyond the visual aspect, would resemble the original instrument in terms of sound to the extent feasible.