Can bending of the Sao be a problem?

General
#1

Today I have more of a theoretical question for anyone who has experience with building shamisen and the properties of wood. I was wondering the other day if the Sao can actually bend in some way after a while.
I was thinking about this since it’s common in the Guitar and Bass world, that the necks can bend a little depending of the temperature and generally with the change of seasons. The changes are minimal, but they can offset string height and overall tuning. To compensate for that problem, there is a so called ‘truss rod’ installed in in the neck, which you can tighten or loosen and adjust the neck this way.

On the Shamisen there isn’t such a thing of course, so I was wondering, do this little changes in the wood really matter on the Shamisen? Can the Sao even get bent that much at all? The string height isn’t really an important factor it seems, considering they can be pressed down fairly easy anyway.

I hope someone can give a little bit of advice on this topic! :slight_smile:

#2

All wood will react to humidity and temperature to some degree, but I think the reason it’s such a big deal with guitars is the string weight and tension. The silk and nylon used on shamisen aren’t going to exert the amount of pressure that wound steel strings do. Also, shamisen are (theoretically) de-tuned and the bridge removed after each session. I’ve yet to meet a guitar player who lowers the tuning on a guitar after playing (unless they intend to store the instrument away for an extended time).

I thought that perhaps kinboso (metal fitting, usually gold) might be used to keep the sao from bending but many internet searches later it looks like it’s only for the joints, that is the kinboso doesn’t extend the length of the mitsuori.

Unless you are somehow exposing the shamisen to quick, extreme changes in temperature and / or humidity I wouldn’t worry too much about the sao bending.

#3

Yeah, string tension makes a lot of sense! Detuning on a guitar is not recommended to keep tuning stability up of course, which isn’t a concern on the shamisen. I didn’t really think about different tension at all, thanks!

It would probably even be less of a concern on a three piece Sao than it is on a single piece one.

© 2020 Kyle Abbott