Mujitsu and Tairaku's Shakuhachi BBQ

Hi Michael.

madoherty wrote:

Some of you may have seen the 1/2 shakuhachi (root-end) on ebay recently.  It is a truly beautiful and well-crafted jiari 1.8 root-end with a plastic joint (also 1/2).  When fitted with the top portion of a Yuu it plays wonderfully, and exactly in tune.

I am attempting to fit the root-end with a suitable bamboo top portion that I am crafting and wanted to poll the Group to see if anyone either had experience with this sort of non-sense, or had some ideas concerning the issues I am having...

Not nonsense at all. I've done three of these before. All were quite unique adventures on their own!

The main issue:  Although the root-end plays great with the top of the Yuu, it is having problems in Otsu, particularly with Ro, Tsu, and Re.  These notes are a bit weak, and also a bit flat (Re and Tsu more flat than Ro).  I am thinking about the mouth of the flute behind the utaguchi as being a possible culprit, but also am wondering if more bore work should be done to just above the joint... or a combination?

I have a feeling it would need a smaller bore profile than that of the Yuu. The first thing I would do is compare the root piece with the bottom section of a flute that is in tune for you, or with the bottom section the Yuu since you are using the top piece. How do the lengths compare? Are the finger holes in the same place or lower than on the Yuu?

Any ideas?

If the sections are the same length and the holes in the same place, it's a bore issue. You may have to fabricate the bore of the entire top section so that it is on the narrow side. Then slowly start opening until the timbre, pitch and volume is to your liking. A smaller top section may bring Tsu and Re up to pitch but may make Ro flatter but it's difficult to say. The Yuu has a slightly wide bore. Many old 1.8s have a smaller taper at the bottom section than the Yuu. Removing the possibility of operator error, this could be the reason why those holes are flat.

Enjoy the trip!
Perry

The bore taper should be pretty much constant no matter what the diameter. Have a look at this profile and work backward from the joint to the utaguchi, so that the taper from the choke point to the joint continues smoothly up until about 10 cm from the utaguchi (see the chart), at which point it should remain constant up to the utaguchi at about 20mm. That should give you a good starting point.

http://www.navaching.com/shaku/bore.html

Toby

Last edited by Toby (2009-04-12 11:57:51)

Hi Michael, Toby is correct in pointing out that there is a taper that narrows consistently as it approaches the root. And that there is a choke point somewhere in the middle between the Tsu hole and the bottom of the root. That concept is a given for the shakuhachi and I assume that it goes without mentioning, but I forget that not everyone may know this.
Also, know that the degree of taper and the exact location of the choke point affect tone color, tuning and response. Some flutes have a more dramatic taper than others. Knowing the difference is when "taste" becomes a larger issue over tuning or response.

If you use measurements, think of it as a guide but know that you should follow your instinct as what you are looking for is not on your map.

Not that this will help you, but here is a photo of the last match I did. I think it was a 1.5.



Playing match maker is a lot of fun...but you can run into personality issues