Woodwind hole placement
Dave Golber
>particular six hole transverse flutes in D and G and a kaval.
>Can anybody supply me with formulae or rules of thumb which
>determine the placement and size of fingerholes for cylidrical,
>conical and combined cylindrical/conical tubes ?
>
Send me $10 and I'll send you numbers for a Bulgarian kaval in D,
plus my pamphlet "How to Play Bulgarian Kaval".
I've made 95 kavals, plus other ethnic instruments.
Dave Golber
3485 Greenwood Avenue
Los Angeles CA 90066
310/391-1269
I'm posting this, rather than mailing the response,
in order to advertise a little.
Iskandar Taib
>I am interested in making my own woodwind instruments, in
>particular six hole transverse flutes in D and G and a kaval.
>Can anybody supply me with formulae or rules of thumb which
>determine the placement and size of fingerholes for cylidrical,
>conical and combined cylindrical/conical tubes ?
I just got some Lexan tubing in from AIN Plastics the other day
and got the bright idea of drilling holes in a length of it and
making a flute. So I'd be interested too...
Wonder if I can get whistle mouthpieces also. These plastics
suppliers have all kinds of acrylic tubing in weird colors and
all kinds of diameters...maybe I'll just fit one mouthpiece to
various tubes.
--
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Iskandar Taib | The only thing worse than Peach ala
Internet: NT...@SILVER.UCS.INDIANA.EDU | Frog is Frog ala Peach
Bitnet: NTAIB@IUBACS !
beth diane garfinkel
>I just got some Lexan tubing in from AIN Plastics the other day
>and got the bright idea of drilling holes in a length of it and
>making a flute. So I'd be interested too...
A couple of anecdotes:
There was a woman at the '89 Boston Early Music Festival, I forget her
name, but she's from Norway, who made a Ganassi soprano recorder out of
clear plastic tubing: she drilled holes at the proper junctions, and
scraped out the proper parts of the inside,and the outside, to create
the fipple, and gave it a wooden block just as she would any other
wooden recorder. Her comment was that the stuff was very difficult to
work with, and that she'd made this one for show, but she wouldn't build
any others because it was too much work. It was neat to play on,
though; you could see the insides getting all steamed up.
I also met a man who bought a renaissance flute made out of a sewer pipe
for about $35 dollars; he says it's one of the best instruments he owns.
Beth
--
"This must be Thursday. I never could get the hang of Thursdays."
-Arthur Dent, on being told that the Earth is about to blow up.
Kevin Dooley
>Also, why are the holes on whistles different sizes?
Well, the two questions "where do the holes go" and "why are they different
sizes" are coupled. The answer to the first question is "where your fingers
fall", and the answer to the second is "given the placement of the holes,
their size is chosen to give the correct pitches". I like to think of the
problem of the acoustics of a woodwind instrument by analogy with electrical
impedance. In many ways they are similar phenomena.
You can easily convince yourself, by playing half-hole fingerings, that
the sizes of the holes is a critical feature in determining the pitch which
sounds. If I cut the flute at some point and set up a standing wave in it,
there is a pressure node in the vibrating air column essentially at the end
point. A very large hole also causes a pressure node, essentially at the
hole. It is as if the rest of the flute doesn't exist (if the hole is large
enough). However, if I put a smaller hole in the flute, the node it causes
is somewhere farther down the pipe. The analogy to impedance is obvious.
If I put an zero resistance shunt across a transmission line, I get a voltage
node and the resulting reflection can be used to set up a standing wave. If,
however, I put a small but finite resister across a transmission line, there
is some reflection and some transmission. It is roughly equivalent to say
that there is a voltage node slightly farther down when calculating the
standing wave's wavelength.
In practise, the hole size and placement on a flute has been determined from
generations of experimentation. As a first approximation, if I were making
a flute, I would take my hollow pipe and blow through it, cutting it to a
length such that the tone produced is the pitch I wanted. Then I would put
my fingers along the instrument at comfortable, fairly even seperations and
mark those positions. Then make a very small hole at the point for the
little finger of my right hand. This hole would then be enlarged until the
pitch which sounded with it open was a major second higher than that of the
closed pipe. Then I would procede similarly for each of the other holes.
Making a flute which would have a nice second register, however, would involve
lots and lots of experimentation in order to get it all on reasonably
accurate pitches taking into consideration the effects of your fingers
on the holes and the difference in air pressure required to get the higher
register.
The practise of flute making is not as easy as it would at first appear.
Kevin
ps. I should say that I am not a flute make, I have never made a flute,
but I have played several woodwind instruments and have made a study of
acoustics.
Al Stavely
>I am interested in making my own woodwind instruments, in
>particular six hole transverse flutes in D and G and a kaval.
>Can anybody supply me with formulae or rules of thumb which
>determine the placement and size of fingerholes for cylidrical,
>conical and combined cylindrical/conical tubes ?
What you *don't* want is formulae, if by that you mean the hardcore physics.
For wind instruments you're talking fluid mechanics, which is *far* more
complicated than (for example) figuring out where to put frets on a string
instrument. Have a look at Arthur Benade's _Fundamentals of Musical Acoustics_
or some similar book if you want to know what you're up against.
My advice would be (1) copy an existing instrument that you like and then (2)
make minor adjustments by trial and error. One thing to notice on flute-type
instruments is that the head joint has to narrow somewhat with respect to
the body if you want a good full tone. Measure the bore of your prototype
carefully!
--
- Allan Stavely, New Mexico Tech, USA
Bob Andrews
>My advice would be (1) copy an existing instrument that you like and then (2)
>make minor adjustments by trial and error. One thing to notice on flute-type
>instruments is that the head joint has to narrow somewhat with respect to
>the body if you want a good full tone. Measure the bore of your prototype
>carefully!
Your Boehm roots are showing. :-) It need not be the head that tapers
("invented" by Boehm ca 1850), but may be a tapering body and foot with
a cylindrical head (as baroque & classical flute, roughly 1650-1850).
The taper functions primarily to get the octaves in tune. A "full
tone" is more a function of the diameter to length ratio. Of course,
an extreme body taper can adversely affect a full tone (which is one of
the reasons Boehm's tapered head & cylindrical body caught on). Note
that most piccolos still have "conical" bodies thought with Boehm
fingerings so that one can stand to be in the same room where one is
being played. :-)
Many (if not most) "folk" flutes are cylindrical, like the European
"Renaissance" flute. To get a second octave in tune, little can be
done with tone hole fudging. Mostly different fingerings must be
employed (actually overblowing on different harmonics). This coupled
with repertoire is why I have settled on the 18th century or baroque
flute as my personal flute of choice.
BobA
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Bob Andrews Ingres, A Member of The ASK Group bo...@ingres.com
Al Stavely
>In article <1992Nov2.1...@nmt.edu> a...@nmt.edu (Al Stavely) writes:
>>My advice would be (1) copy an existing instrument that you like and then (2)
>>make minor adjustments by trial and error. One thing to notice on flute-type
>>instruments is that the head joint has to narrow somewhat with respect to
>>the body if you want a good full tone. Measure the bore of your prototype
>>carefully!
>
>Your Boehm roots are showing. :-) It need not be the head that tapers
>("invented" by Boehm ca 1850), but may be a tapering body and foot with
>a cylindrical head (as baroque & classical flute, roughly 1650-1850).
>The taper functions primarily to get the octaves in tune. A "full
>tone" is more a function of the diameter to length ratio. Of course,
>an extreme body taper can adversely affect a full tone (which is one of
>the reasons Boehm's tapered head & cylindrical body caught on). Note
>that most piccolos still have "conical" bodies thought with Boehm
>fingerings so that one can stand to be in the same room where one is
>being played. :-)
Well, I didn't want to go into a lot of detail, but I meant my comment to
apply to conical-bore flutes too. It works to have the head joint less
tapered than the body, or cylindrical, or even tapered in the opposite
direction! But yes, a cylindrical head-joint does seem to be the standard for
conical-bore flutes.
The narrowing of the head joint does help improve the tone color, for the same
reason that it gets the octaves in tune: you want the second and higher peaks
in the frequency spectrum to be at exact multiples of the fundamental
frequency. But you're right, getting the octaves in tune is another important
reason for getting the tapers in the right proportion.
Iskandar Taib
>>>make minor adjustments by trial and error. One thing to notice on flute-type
>>>instruments is that the head joint has to narrow somewhat with respect to
>>>the body if you want a good full tone. Measure the bore of your prototype
>>>carefully!
Is this more or less what you mean?
hole where one
blows
v
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joint area
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head?? body?
This should be childs' play with lexan or plexiglass/perspex tubing! The
head can be two layers nested together and glued... the joint area is
simply a the inner tube extending beyond the outer tube.
Dave Golber
>>>>My advice would be (1) copy an existing instrument that you like and then (2)
>>>>make minor adjustments by trial and error. One thing to notice on flute-type
>>>>instruments is that the head joint has to narrow somewhat with respect to
>>>>the body if you want a good full tone. Measure the bore of your prototype
>>>>carefully!
>
>
>head can be two layers nested together and glued... the joint area is
>simply a the inner tube extending beyond the outer tube.
>
This is generally considered _baaaad_.
Better than this would almost certainly be just plain straight tubing.
Not quite the place to get into the whole thing of "how do wind instrument makers
actually make tubes with variations in the bore?"
Dave Golber
J. Lani Herrmann
there is a nice easy to read text by Trevor Robinson, The Amateur Wind
Instrument Maker (rev ed) published by the U of Massachusetts Press in
1980. He mentions a number of other authoritative texts, including the
Galpin Society Journal. A French scientist named F. Leipp has written
a definitive text on musical acoustics (alas, not yet to my knowledge
translated), and his lab in Paris investigated the acoustics of various
instruments from the player's point of view as well as the acoustic
end of things; they published a mimeographed monographic series. I'm
not sure if he and his lab are still around; it used to be the Labo.
d'Acoustique, Universite' de Paris VI (Faculte' des Sciences de Paris).
(oops, that's _E_ Leipp.) His assistant, a Mlle Castellengo, might
still be working there. His book, Acoustique et Musique, was published
in 1971 by Masson & Cie, Paris.
Sorry, I should have put a paragraph break in there.
Iskandar Taib
Well, it wouldn't be all that difficult to chamfer the inner
tubing so that you end up with a tapered end.. if one doesn't
have a lathe a sharp knife would do as well, or a tapered stone
on a dremel. Then you'd sand it smooth and perhaps buff it so
everything is nice and transparent...
Dana S Emery
nt...@silver.ucs.indiana.edu (Iskandar Taib) wrote:
>
> This should be childs' play with lexan or plexiglass/perspex tubing! The
> head can be two layers nested together and glued... the joint area is
> simply a the inner tube extending beyond the outer tube.
No, the amount of narowing needed is quite small, in fact it is so small in
historical instruments as to invite conjecture as to wether it was
intentional. A built up layer of shellac/polyurethane can be used to
effect this much more reasonably than tooling it, especially for unica.
About 1 part in 50 (dia) comes to mind, mostly near the foot (I think from
the 3rd hole down past the 1st to the foot).
Yes, smoothnes of bore is a paramount concern for good tone, it is usefull
to undercut the holes as they meet the bore, in order to discourage
turbulence. As this has different effects on the fundamental pitch and
upper octave pitch, it must be integrated into the design.
Metal and plastic flutes are much more easily smoothed than wooden ones,
but they all need it.
--
Dana S Emery <de...@umail.umd.edu>