After a review of the structure of wood concerning its acoustic properties and a discussion of the merits and demerits of wood as a material for making soundboards of stringed instruments, the effects of three chemical treatments (a low molecular weight phenolic resin treatment, a resorcin/formaldehyde treatment, and a saligenin/formaldehyde treatment) on the acoustic properties of Sitka spruce wood are reported and compared with those of formaldehyde treatment. All three chemical treatments increased the specific dynamic Young’s modulus and greatly decreased damping (tan δ) without greatly increasing specific gravity. The range was almost equivalent to that with formaldehyde treatment whose superb effects have already been confirmed in the violin. With saligenin/formaldehyde treatment, the frequency dependence of tan δ could be controlled over a wide range by changing the saligenin concentration. In all treatments, hygroscopicity was reduced and dimensional stability was improved significantly.