Anatomy and mechanical properties of woods used in electric guitars

Abstract

ABSTRACT Many endangered tropical hardwoods are commonly used in electric guitars. In order to find alternative woods, the current electric guitar woods need to be studied and classified as most research in this field has focused on acoustic instruments. Classification was done based on luthier literature, woods used in commercially available electric guitars, commercially available tonewoods and by interviewing Finnish luthiers. Here, the electric guitar woods are divided into three distinct classes based on how they are used in the guitar: low-density wood used in the body only (alder, poplar, basswood, ash), medium-density wood used in the body and neck (maple and mahogany), and high-density wood used in the fretboard only (rosewood and ebony). Together, these three classes span a wide range of anatomical and mechanical properties, but each class itself is limited to a relatively narrow parameter space. Statistically significant differences between these classes and the average hardwoods exist in the wood anatomy (size and organization of vessels, fibres, rays and axial parenchyma), in the mechanical properties (density, elastic modulus, Janka hardness, etc.) and in the average price per volume. In order to find substitute woods for a certain guitar wood class, density and elastic modulus can already be used to rule out most wood species. Based on principal component analysis of the elastomechanical and anatomical properties of commercially available hardwoods, few species are similar to the low- and high-density class woods. However, for all of the three electric guitar wood classes, non-endangered wood species are already commercially available from tonewood retailers that match the class characteristics presented here.