Acoustical properties of wood in string instruments soundboards and tuned idiophones: biological and cultural diversity.

The acoustical properties of wood for instruments have mostly been studied on a few archetypal woods in Western musical instruments. The objective of this paper is to extend knowledge on the diversity in wood properties and uses in instruments from different geo-cultural areas. A wide set of data has been collected on vibrational properties of 452 species, through experiments and literature survey. Property distributions within broad categories confirm the known characteristics of softwoods, but also evidence specificities of tropical hardwoods compared to temperate-zone species. A relational database has been created to link wood properties and uses in musical instruments of the world. Two case studies on acoustically important functions in different geo-cultural areas show contrasted trends: (i) species used for xylophone bars and slit-drums in different continents all share a very low internal friction, (ii) on the contrary, the only characteristic common to soundboards' woods is a lower than average density, whereas their acoustical properties differ widely between them and with the "Western" standard in wood choice. All these materials being nevertheless adapted to their context, cultural specificities in the structure, playing mode and "sonority" preferences should also be taken into account.