Sort:  

The hardest part of playing the shakuhachi is making the sound. It is edge-blown and has a very big hole that has to be partly covered by the lower lip. You can see it here:

The scale does give some limitations, but I think that it comes intuitively when you are used to the 12-step scale. You can bend the tone by simply changing the angle of your head - as much as one whole in both directions, so it is surprisingly versatile.