The hardwoods used for a guitar’s back and sides (the same species is used for both) contribute rigidity and stability to an acoustic guitar body. This helps generate more sustain from notes as they ring out. The back and sides woods also emphasize certain resonant frequencies in ways that add unique sonic colors and textures to the guitar’s overall sound.
Along with body shape and top woods, the woods used for the back and sides of an acoustic guitar play a key role in coloring the guitar’s voice. Hardwoods, such as rosewood, mahogany, koa and maple, are exclusively used. They provide the supportive shell of the guitar body, and their hardness and density add the rigidity that helps generate sustain from the notes.