I’m a beginner looking to build my own tsugaru shamisen and I was wondering if it really mattered what kind of wood you use for the Sao. I read that, the duo has to be Karin, but I can’t find anything past that. More specifically, would I be able to use walnut for the neck? I recently got a ton of walnut and. I wanted to know if I could use that to make it unique and save a buck at the same time. Thanks guys!
Howdy, Konrad. Welcome to Bachido!
Traditionally, karin wood is commonly used for the dou, but you can really use any wood you want. I’ve used maple, east indian rosewood, padauk and bloodwood and they’ve all worked well. If you have an abundance of walnut, then definitely use that! 
If you haven’t already, you might be interested in my book, Shamisen of Japan. It includes step-by-step instruction for building shamisen, as well as templates to trace onto the wood - http://bachido.com/products/shamisen-of-japan
Good luck, and please keep us updated with pictures!
So you think it would work for the dou too? Good to know. Thanks, Kyle.
Oh yes, probably even better for the dou than the sao (though that’s fine too). In a way, slightly softer wood is better for the tone than hard-hardwood (like kouki or such). That’s why even for “kouki tsugaru shamisen”, the dou is still made from karin.