Jim, looks like a wonderful project to be involved in. Wish I were part of it. No argument from me on the bass. The original poster just wondered if it was OK to use pine instead of spruce since all the sizes he needed were available in it. Those of us who are lucky enough to have a wood shop have a great advantage. For myself I just set aside clear spruce and pine that comes mixed with common construction lumber. No problem to get bass in 4/4 and 8/4 thickness here but it takes a stack of money of equal height.