Mujitsu and Tairaku's Shakuhachi BBQ

Toby wrote:

As far as feeling the bamboo vibrating. I think you will find that you mostly feel the vibrations in your fingertips as they cover the holes, and not on the body of the flute itself. Try this: have someone else play a flute whiloe you grab the body between your fingers. How much do you feel the vibrations now?

Some years ago, I use to play some bamboo transverse flutes I made, and one day I told a friend about the taste of stay feeling the flute vibrating trhough the arms... He, a guy who don't play any instrument said "ohhh I would like to feel that"... I said "hold the flute with your two hands and I will play to you!"... and so we did... his smile when I started to play could tell me that he was stoned, but he wasn't. After that, he told me that he felt almost the same thing I did...

I like the science thing...I like the feeling thing...



Discussions will always occur among these.



A short history well known of most people:

Zhuangzi and Huizi were strolling along the dam of the Hao Waterfall when Zhuangzi said, "See how the minnows come out and dart around where they please! That's what fish really enjoy!"
Huizi said, "You're not a fish — how do you know what fish enjoy?"
Zhuangzi said, "You're not me, so how do you know I don't know what fish enjoy?"
Huizi said, "I'm not you, so I certainly don't know what you know. On the other hand, you're certainly not a fish — so that still proves you don't know what fish enjoy!"
Zhuangzi said, "Let's go back to your original question, please. You asked me how I know what fish enjoy — so you already knew I knew it when you asked the question. I know it by standing here beside the Hao." (17, tr. Watson 1968:188-9)

Toby,
Love your avatar and title!
How true it is and funny!

Kiku Day wrote:

Toby,
Love your avatar and title!
How true it is and funny!

I don't know who posted them...Someone with a sense of humor at least...

Musgo da Pedra wrote:

Although I do not have anyone to play a shakuhachi while I hold it's body, I tested it by myself, playing Re and holding diferent places of the flute. So, I can say: Yes I can feel it on shakuhachi. Even the worst flute I have vibrates.

Henrique,
You can not do this test by covering ANY of the sound holes with your fingers, because your fingers will feel the vibration comng OUT of the sound
holes. You must either play the flute while someone else feels the shaft, or you must cover up all the sound holes with tape, then play the flute withot touching the taped holes.

Musgo da Pedra wrote:

Toby wrote:

I have a number of good bansuri and other thin bamboo flutes, and indeed one can feel the body vibrating. Can you feel it in a shakuhachi?

Although I do not have anyone to play a shakuhachi while I hold it's body, I tested it by myself, playing Re and holding diferent places of the flute. So, I can say: Yes I can feel it on shakuhachi. Even the worst flute I have vibrates.

Toby wrote:

I love bamboo and everything about it. No plastic or metal flute gives me the same feeling. But that's not what we are discussing here. If we were talking about the experience of playing, that would be a different matter.

We are talking about sound and about playing. When we play, we can play only for ourselves and/or for people or we can be aware that we play  not only to for ourselves and/or for people but to every being who can listen, and maybe to some things that do not have ears... I know that I sound foolish with that, but is how I feel the thing...

We can't hear dog whitle...it is not a sound? We can't hear harmonics on high pitches, but we can in low pitches... the very very low pitch of the bamboo vibrating and it's harmonics should be heard by some being. Do not exist some animals who can hear very low frequencies?

The question here, about the material and it's activity in sound production is concerned to human ears. This is ok to me... If we consider that sound is vibration, and that there exist a lot of frequencies that we can't hear, every litle thing matters... Also, everything that vibrates produces sound right?!  So the material matters...


I agree that my thoughts can not be pratical and that the material vibration in flutes will not produce sound as in a string instrument for example. You are right about the fisic works...




Toby, do you think that there is a way to measure the frequency of the material vibration on a flute, I mean separeted from the main sound? It would be nice!


Also ,IF we find a way to stop the material vibration, I would like to hear how different the same flute could sound, with vibes and without them (maybe in the future we can have an extra button in the shakuhachi  Knob-u-Ryu: Vibes on/off)... euhieuhe 



Everything I said can not make sense, because I have a bit of dificult to express myself with my language limitations and also because I am a fool on the hill...


A big hug man!!!


Peace!

Let's just say that as far as sound goes, the vibration of the material does not influence the sound that comes out of the flute in any way that is perceptible. A scientist named John Backus did measurements of the vibration of the wooden clarinet body with accelerometers. It vibrated by expanding the bore by about 1/1000000 of a meter. That gives a radiated sound from the body of -40 dB, that is WAY below the threshold of perception.

As I said, some French researchers did an experiment with a very thin metal tube, even at 15 micrometers, it would not vibrate much, so they forced it to vibrate by making it elliptical, so that it REALLY vibrated. They did very accurate and fine spectral analyses, and could not find, nor hear, any difference in the sound when the tube vibrated quite a lot and when it didn't.

Toby

Taldaran wrote:

So in theory, if you applied a very thin hard coat of epoxy over a perfect match of a master made shakuhachi, but molded out of paper mache, it would sound the same? I have already heard many people say the Yuu does not sound like bamboo. How much less would paper mache?

Just for fun, I made a shakuhachi out of a thick cardboard tube used for textile rolls from a fabric store with almost the same dimensions as one of my first PVC, and entirely coated it with the same water based polyurethane as I use on some of my bamboo bores to produce a smooth hard finish that would repel the moisture from my breath. I also soaked the utaguchi edge with superglue and sanded it smooth. It felt as hard as an inlay.

It functioned about the same as my PVC flutes, but it sounded muffled, dull and empty, (and not a good empty either).

Ken and Brian talk about the "glow" produced by the taimu. Some would say that it is the soundwaves getting bottled up and taking extra time to exit the flute, but the speed of sound is fast, and the flute is not that long.

I suggest that it's the bamboo itself that is storing the soundwaves like a spring (potential energy), and then releasing it after the event.

Even striking the flute with your knuckle will make a pleasing knock that depending on the bamboo will continue to vibrate. Think of long bamboo windchimes. No blowing involved. The residual sound is the bamboo itself vibrating.

That makes the bamboo tube an ideophone.

What many people fail to understand that even if a piece of bamboo is fomed into an aerophone, it still continues to function as an ideophone. The oscillations of air also strike the wall of the flute sounding the material. Hell you can feel the soundwaves striking your fingertips especially on flutes with bigger holes. On long flutes it can almost tickle!

It's not just the empty space. The material counts.

One of the main factors in bore geometry is smoothness. There is a boundary layer effect, in which at a certain distance from the wall, air molecules are slowed and their energy robbed by viscous and thermal losses. The rougher the bore, the more the loss. Was the inside of your cardboard tube as smooth as PVC? Since 99% of the energy input is lost before any sound is radiated out of the flute, most of it at the walls, you do want them to be as smooth as possible.

In terms of the idiophone/aerophone thing: The vibrations that you feel when you tap the flute with a finger are distortional vibrations, caused when the tube is deformed by being struck at a point. The air column creates NO vibrations of this kind; rather it pushes the walls out equally around the inner circumference. wall. The only way that the air column can make the walls vibrate is by expanding them--like blowing up a balloon. It is that kind of pressure wave that you feel on your fingertips. Fingertips are soft. Wall materials are not, and highly resist being "tickled".

Toby

At us conversations on these themes too are conducted. Usually I compare plastic shakuhachi with plastic  the woman:)) which has a number of obvious advantages. But at all thus, for the normal person the-choice is obvious.) I consider what better to play on a bamboo flute on the first register, than on the plastic let even decently made.

I base nothing on absolutes, but all physical objects have consistent properties. I'm sorry that I wasn't clear enough about what I meant with "coupling", so let's clear that up.

All materials have resonant frequencies, at which they can vibrate and the vibration is sustained in a way that can allow it to grow until limiting factors set in, just like pumping your legs on a child's swing in the park. If you pump your legs at a frequency that is different than that of the swing and chain, you never get very far, do you?

In solid materials, resonant frequencies depend on many factors, but the main ones are the hardness of the material, its thickness and the form.

Now let's talk about flute bodies. For the flute to vibrate significantly, in what is called "breathing mode", it must have one or more resonance frequencies that can be excited by a significant playing frequency (either the fundamental or one of the stronger partials). Not only that, it must be able to sustain that vibration, which is what symathetic vibration is all about.

This can happen with walls the thickness of those of the shakuhachi only if the material is flat--forming even a very thin metal tube into a circular cross-section raises all the resonant frequencies way beyond any playing frequency. This means that even if the air column is pulsing against the sides of the tube, it cannot create a sympathetic vibration in the walls. And the air pressure variation is far too small to deform the tube enough to matter at all.

But fingers are an entirely different matter: they are soft and therefore the relatively small air pressure variations in the bore cause the pads of the fingers to flex, and that is what you are feeling. The fingers and the bamboo are of quite different levels of hardness. If you doubt this take a stream of water out of a high pressure nozzle and aim it first at a piece of bamboo and then at the tip of your finger. Which deforms more? In fact, can you see any deformation in the bamboo at all? Not only that, your finger has considerably lower resonance frequencies than a piece of bamboo, even a relatively flat piece of bamboo.

If the flute tube were as soft as your flesh, it would most certainly vibrate significantly, and not to the advantage to the sound or response.

Toby

Last edited by Toby (2009-12-24 23:03:47)