This perspective is mainly aimed at the beginner who needs some basic images of what he /she is getting into when undertaking the study of shakuhachi. It could also be useful for teachers to pigeonhole the general aspects of playing shakuhachi.
I hear people talk about shakuhachi being difficult to play. This is true in the beginning but there's need to think this way forever. Gaining confidence in the beginning is about appreciating the small steps and building on your experiences. You can also gain some confidence by just knowing the "nature of the beast", so to speak. Shakuhachi is a "lazy" instrument so you have to do all the work! You probably have noticed early in your playing experience that there are NO LEVERS on the shakuhachi to push and pull to help you change the pitches, like on a clarinet or sax. There also are NO CHAMBERS in the shakuhachi nor an external bag like bagpipes to help in the breathing. Also, there is no mouthpiece to help you in making sound, just a blowing edge. So, here's why it's difficult at first to play:
1) we have to make the breathing apparatus with out own body;
2)we have to create levers to move around with our fingers and head movement;
3) we have to develop the mouthpiece(s) to use for creating different sounds.
Let's look at these one at a time.
#1. No chambers: you'll have to learn belly breathing. You'll also have to learn correct/effective posture and how to hold the shakuhachi. Even if you have been meditating for years, or singing you'll have to learn how to breath WITH the shakuhachi in your hands and up to your mouth. In other words, make it shakuhachi specific. Learning to belly breath will come sooner than you realize but it won't show up as a result to really effect influence sound for a while. You'll have to learn how to keep your throat open and where to put your tongue. Patience!
#2. Once you have some consistancy with sound and begin playing sounds you will learn how to manipulate the sound using your fingers. You'll be doing what's called "half holing" and "shading", sometimes at the same time on two different holes while at the same time moving your head up and down and/or to the side and in circles. These finger movements will need to be very efficient and effective so that you can do the same movement again and again so as to get the same desired result. We have to make the levers we use in playing. Of course, it's very personal since your fingers are going to become these levers and you'll learn to enjoy this aspect of shakuhachi very much. It's another place where you and the bamboo are becoming one together. There are ways to do this that an accomplished teacher can show help you with. Don't overlook this aspect of playing either as it will haunt you until you give it the attention it needs and deserves.
#3. The mouthpiece. Just as in #1 & #2, you'll have to make a "mouthpiece" that helps you achieve your desired goal of making certain sounds. Or, just one sound at the beginning. Most people will form an embouchure from doing whatever it takes at first to make a sound. Then, since it was successful they continue with this. That's about all one can do at first but soon after getting consistent sound you'll need to start taking a close look at this embouchure and seeing if it is really effective as could be. Thinking natural it probably isn't since you haven't been playing shakuhachi very long. You'll need to use a mirror and also get much advice from your teacher concerning this, if the teacher is willing to help you. Some teachers prefer to let you go at it yourself in the trial and error method. In the end, you'll do that anyways but there are some useful tips on this aspect of playing that could help you not "reinvent the wheel". It's best to get help with this early as most stubborn people wait to long thinking they can do it themselves and end up with bad habits.
The 4th area of concern will be in learning to read the scores. Approach this as one would to learn a language. So anything you can do to use the language more makes you better at it. Write it down over and over; read it; say it out loud; sing the songs out loud, etc.
In a nutshell, you can see that all of these areas of focus mean that you have to make something with your body that doesn't exist yet:
1. A breathing apparatus with chambers (lung, wind pipe, belly movement, etc).
2. Levers to push and pull with your fingers.
3. Mouthpiece(s); (using your lips, chin teeth, bones, tongue position, etc.).
4. Learn some basic japanese.
Now you know why it's difficult at first. We are lucky to get any sound at all. However, these things can all be done. This is why you should have confidence that it's not going to be difficult forever. You have to tell yourself that you will be able to effectively create all these things and then you'll be able to enjoy playing very much. So, enjoy creating these and making shakuhachi part of you and you part of it.