Mujitsu and Tairaku's Shakuhachi BBQ

jaybeemusic wrote:

Hey guys...

do any of the makers out there even consider tone/timbre when doing bore adjustments?


i know that bore diameter effects the pitch but.... is it possible to change the tone while keeping the note the same?

just a thought.....

jacques...

Jacques,

I adjust the bore for tone and timbre more often than for pitch. This is especially the case for thinner bore shakuhachi.

For jinashi shakuhachi, I first open up the bore and adjust for the best ro tone possible. If ro otsu and ro kan are in pitch, I drill the holes. Then, I might do a little more tone adjustment in the bore if needed before the holes are fine tuned. I find the pitch can usually be adjusted by undercutting the holes. On wide bore flutes, the upper kan register sometimes needs some bore work to improve the pitch. There are also other occasional instances where bore work is needed to adjust pitch. However, if possible, I like to keep things simple by adjusting the holes for pitch and the bore for tone. Of course it doesn't always work out that way. Sometimes a combination is needed.

I think it's possible to change tone while keeping the note the same to some degree but it depends on the exact spot in the bore. Personally, I find it more difficult to work in that direction.

Ken

Hi Jacque,

jaybeemusic wrote:

Hey guys...

do any of the makers out there even consider tone/timbre when doing bore adjustments?


i know that bore diameter effects the pitch but.... is it possible to change the tone while keeping the note the same?

just a thought.....

jacques...

Nearly all my spot tuning is done for timbre and/or response. In my experience, getting the holes in the right place first is one of the most important steps to making a solid playing instrument. If the aspect ratio is near ideal, the flute will work properly. Some amount of pitch can be dealt with by by adding and subtracting material in the bore but any amount work inside will have a greater affect on the timbre and response on the flute than it will the for the pitch of that particular note. For example, if a note is very flat in Otsu and you add a huge gob of filler to the middle of the resonance spot, it will sharpen the note, but will dramatically change the tone color and response of other notes. Especially notes with pressure points close to it (Kan or Otsu).

It would help to make pressure point map of the entire flute to see what points overlap. And then do tests with the different sized tuning beads to try things out. Then keep a note book of your discoveries. One day, you may have a very valuable note book (if only Antonio Stradivari kept one!)

Toby wrote:

The intonation of jiari flutes depends in large part on the correct bore profile no matter what the hole position (at least in terms of correct intonation of the octaves and harmonics and response up higher, which is related), but the overall diameter has a great effect on the timbre. This can be adjusted while keeping the geometry correct for intonation (by enlarging or reducing the whole bore while keeping the same shape). In addition there is much that can be done in this direction in the upper part of the bore, which corresponds to the headjoint on a concert flute. A great deal of the global character of the sound originates there, and adjustments can be made to it (to some extent) which change the timbre without overly affecting the intonation, although response in the third octave especially can be tricky.

Right on Toby.  A couple of weeks ago I replied on a thread concerning the difficulty of Hi Go on a 1.6 Gyokusui. I found three spots that had the most affect on the playability of the note; the top of the flute, at the top Kan pressure point and slightly under the thumb hole. I worked back and forth between the three areas because once an adjustment is made, the other areas will have a different amount of influence (in some cases, a new spot will reveal itself).  This was done slowly to make sure the note got better, more accessible and  without changing the character and response of other notes.

I also sent it back for feedback once I felt the adjustment was objectively successful. I could have done more but in a Buddhist shakuhachi fine tuning approach,  less is more I'm happy to report that the owner is happy with the work.

Enjoy peering into the tube! Perry