I often use Adirondack spruce soundboards on dulcimers with walnut back and sides.
Adirondack spruce was used for the soundboards of many classic fretted instruments made before World War II. It was also used to build airplanes and in other applications requiring a strong, light and stiff timber.
Adirondack spruce was over-cut and for many years was not readily available. It is slowly making a comeback thanks to careful forest management.
Like many old books the full title is somewhat long; you can get the book at the always wonderful Internet Archive:
