I doubt anyone has found a source for Kouki wood in the US. One problem is that it is endangered; the other is that Kouki is a Japanese name. A cross reference for wood names would be helpful, perhaps in the “Learning Center”. Along with the Japanese common names, Chinese and Western names should be included. The list should be based on the botanical name, since common names are often applied to multiple species. Here's some inputs:
Dalbergia luovelii: (China) lushi heihuangtan, hei suanzhi, (large-leaf) zitan; (UK/US) Rosewood
Pterocarpus indicus: (Japan) Karin; (UK/US) Amboyna
Pterocarpus santalinus: (Japan) Kouki; (China) tanxiang, (small-leaf) zitan ; (UK/US) Red Sanders, Red Sandalwood (NOTE: not to be confused with genus Santalum, aromatic Sandalwood)
Pterocarpus soyauxii: (UK/US) African padauk, African coralwood
Mechanical properties such as strength and hardness might be added as well.
Recently, local woods are starting to pick up favor. Only very slightly (because the desire of endangered are still locked into the paradigm), but fortunately, Japanese newcomers to shamisen don't care about fancy wood and would prefer simple local woods. So, I think eventually all shamisen will move in that direction. :-)
thank you, kyle! with thinking about the long time the japanese lived in a self chosen isolation, i wonder if the first shamisen were made from local wood. have you ever seen such an “early” and historical shamisen?
would european oak be decend to make a shamisen out of? (it is the most available here in the Netherlands)