Mujitsu and Tairaku's Shakuhachi BBQ

World Shakuhachi Discussion / Go to Live Shakuhachi Chat

You are not logged in.


Tube of delight!

#1 2006-07-30 02:20:53

scook
Member
Registered: 2006-07-25
Posts: 5

automatic hole calculator

What do you all think of this:

http://jeremy.org/music/shakutool.cgi

Accurate? Trustworthy? Would it work with non cylindrical bores or just PVC?

Offline

 

#2 2006-07-30 05:32:14

evan kubota
Member
Registered: 2006-04-11
Posts: 136

Re: automatic hole calculator

It's a pretty good start, especially if you carefully measure the wall thickness as an average and find the average inside diameter. No calculator (even for ostensibly constant size PVC) is going to be completely accurate for this sort of thing.

Offline

 

#3 2006-07-31 00:07:29

Karmajampa
Member
From: Aotearoa (NZ)
Registered: 2006-02-12
Posts: 574
Website

Re: automatic hole calculator

I simply use a regular calculator and get percentages of the length.
hole 1 = 78%
hole 2 = 68%
hole 3 = 58%
hole 4 = 48%
hole 5 = 41%

Average hole diameter = 10mm. varies from 9.5mm to 11mm.
Fine tune using hole diameter though you can only raise the pitch.

Kel.


Kia Kaha !

Offline

 

#4 2006-07-31 09:32:45

John Roff
Member
From: South Africa
Registered: 2005-10-21
Posts: 50

Re: automatic hole calculator

Hi Michal

I use the following percentages, which i have had made into a table with measurements from 30 cm to 100 cm.

0.4315
0.4934
0.6079
0.6923
0.7880

Once I have made the measurements and marked them on the flute, I move them up towards the mouthpiece, depending on the internal diameter. I go on an idea that length to internal diameter should be about 23:1. If the diameter is wider, then I move the holes up as much as 2 cm on long flutes (over 65cm). On average, I put the holes about 1 to 1and a half cm closer to the mouthpiece than the above measurements. I start small (5 or 6 mm) with the holes, and make them bigger to get the tuning right.

This approach has lead to some disasters, but usually works out. I suggest you experiment a lot. I use the same measurements for conical and straight bore flutes, as well as for side-blown flutes. On the latter, I leave out the thumb hole, and overblow to jump the octave.

I wish you well with what you are doing.

One thing I find important - If I am tense and getting very uptight about getting a particular flute absolutely right, it often doesn't work. I find my hearing is out and I can't 'make' it work. But if I relax and enjoy the process of making the flute, it's much better, and I remember this is a continual journey of discovery.

Take care

John


'Concepts create idols; only wonder grasps anything.' - Gregory of Nyssa

Offline

 

#5 2006-07-31 10:47:25

Karmajampa
Member
From: Aotearoa (NZ)
Registered: 2006-02-12
Posts: 574
Website

Re: automatic hole calculator

Michal wrote:

karmajampa, this percentages get on conical or cylindrical bores?

By 'conical' do you mean 'tapered' ?
If so yes, I use the same percentage distance from the mouth end, also making sure that the distance for the rear hole 5 is measured from the same point as the front holes. I may measure before I complete shaping the chin rest.

I don't like oval shaped culms/bores, I have tried a few but find them uncomfortable.

There is generally some fine tuning, shorter flutes seem to be less tolerant and more difficult to get the Kan register correct, for me at least, so I like lengths from 1.8 to 2.4 That is 545mm and upwards.

You must make some to put all this to the test, as you will learn much from the doing, to quote, "satisfaction is in the doing" once you have done it, you want to do something else !

Kel.


Kia Kaha !

Offline

 

#6 2006-08-01 01:24:17

waryr
Member
From: Leesburg Florida
Registered: 2005-10-10
Posts: 70

Re: automatic hole calculator

What do you do with the aspect ratio????


If you understand, things are just as they are, if you don't understand, things are just as they are.

Offline

 

#7 2006-08-01 01:56:46

Karmajampa
Member
From: Aotearoa (NZ)
Registered: 2006-02-12
Posts: 574
Website

Re: automatic hole calculator

waryr wrote:

What do you do with the aspect ratio????

What are you asking in particular ?
A high aspect ratio will favor the higher tones, a low aspect ratio the lower tones. I like it somewhere aroung 28-30.
When I am collecting my culms I use this as part of how I select any particular culm. how does the aspect ratio feel for this culm up to the seventh node.

To date, I have not made any major adjustment to the basic formula for hole placement, but every culm presents its' own idiosyncratic issues. It is usually the Kan register I have a problem with, but the majority of flutes, if the Otsu is good the Kan is good as far as fundamental pitch goes, volume may differ, this is another issue usually to do with bore diameter and hole design.

Does that answer your question at all ?

I am not much more than a novice myself.

Kel.

Last edited by Karmajampa (2006-08-01 02:07:35)


Kia Kaha !

Offline

 

Board footer

Powered by PunBB
© Copyright 2002–2005 Rickard Andersson

Google