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That is certainly true, and the comparison by itself doesn't work very well.
My post was in answer to the original post topic by saxpiece, where he compared (most) string players accepting scientific explanations of their musical experience; to (some) sax players not accepting scientific explanations of their musical experience.
My point being that scientists separating one aspect of acoustic property; making a broad statement of musical sound production fact; with the assumption that no musician can have a music making experience that is not completely explained by their laboratory findings; is naive.

And at the same time making similar assumptions about a universal sound produced by a specific material is also (IMO) naive.
Materials do not make musical sound. Musicians do.
Like you said, it's subtle. Subtle nuance is well loved (by some) in music.
Sounds a bit like the 'guns don't kill' argument.

Science is about understanding, so for those of us interested in understanding how instruments work, the science is important. It may not matter to a musician, but then musicians will go round saying stuff like 'bronze is warmer', so an understanding of acoustics should be useful.

With a violin or guitar the string vibrations pass though the body to cause the large body of air inside to vibrate which makes audible sound. The material and it's vibrations have an effect on the sound.
In a sax the mouthpiece and reed directly cause the body of air inside the instrument to vibrate. That's the difference. Any vibrations in the body are caused by the air vibration, not the other way round.

The wall vibrations of clarinets may be 1micrometer but a sax is a bit more around 5, I think.

A scientific model is not reality. Our scientific understanding is subject to finding where the model fails. Newton had an understanding of gravity which is correct, but it doesn't explain every aspect such as why it causes light to bend. Einstein's theories answered that one, but we still don't know everything about gravity. That doesn't mean we are wrong.

In science you use observation adn then you have experiments to test the observations.
Most musicians will play on different instruments and say they hear something and make conclusions. That is just the observational stage. Scientists go on to do the experiments making proper comparisons between materials, similar Pete's tests, but usually much more thorough. Under such testing it is hard to find any evidence of different materials making different sounds in woodwinds.
Why should that be a problem? It's only a problem because musicians have for years believed otherwise. The science says those subtle nuances are most likely due to bore variation etc. Why is that so difficult to accept? Musicians only ever do the observation stage and think that is enough. The science userps musicians ideas because it is a much more rigorous test.
 

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There is a possible dogma that drives science; the need to come to conclusions, even in the presence of inconclusive results.
An exception might be the independently wealthy scientist philosopher. (The truth of physical behavior is emptiness)
Inconclusive results are relevant. It may mean a particular idea has failed to show up. If something works it should show up in tests and the results would not be inconclusive.

"Insignificant" is a gentrified translation of "I'm not sure".
No, it means there is something there but too small to matter. It is considered not to matter because the effect is below the threshold of hearing i.e. it is inaudible.
This is more accurate than saying 'there is no effect'.

If it had been ten sax players that couldn't tell the difference, would it have proven that there was no wall vibration effect on sound?
Here on SOTW, failure by sax players to correctly identify a difference usually proves that there is no difference.
You're not doing a scientific test. You're not testing wall vibration.
The tests done on here are just to see if people can spot the difference. Time and time again people say they can hear a difference in sound between different materials. When presented with just audio clips people can't correctly identify the material. That shows that the effect of different materials is not significant enough to be identified.
It does not say how much the walls vibrate.
 

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A number of Acoustic Science independent researchers have picked up the Flared Bell effect being noticeable in frequency analysis but the effect of wall body vibrations on the standing wave have repeatedly been found to be very minimal by numerous independent researchers.
There are a lot of test done that probably never got written up. I remember hearing about a trumpet being encased in concrete - it still sounded like a trumpet.
When I was at college studying instrument repair we were told about bell rims being significant and all teh different modes of vibration that a bell rim went through. They reckoned material at the bell had an effect on tone but tests done since deny that and the concrete trumpet too. Also there have been several rimless bell trumpets made since then.
I remember hearing about a sax playing playing mouthpeices made to the same dimensions but of different material. The audience couldn't tell them apart. I don't think that was ever written up. The students at Edinburgh University do all kinds of research but only some of it makes the headlines or gets published.

Instruments are traditionally made through trial and error. Stradivari thought violins should be longer and made them bigger and bigger until returning to the size we used today. Our science teacher was involved with harps. He applied some science to determine a particular piece of harp design and found the design was spot on what the science calculations showed it should be. That might not be surprising, but in other areas science has improved things like bell design which has been going on a long time.

This supposed conflict between science and musicians crops up with wind instruments.
 

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My point is that the significance or insignificance is decided by the scientist. Any subtle influence or adjustment to the sound production potential of a musical instrument may be significant to a musician. A scientist is unlikely to have as much investment in the subtleties of sound of a saxophone than SOME sax players have. Numerous scientists have tested the effects of materials. Some say there is no effect, some say the effect is insignificant.
There is a vast difference between zero and some.
That's fair enough. I've said something along those lines before. Scientists maybe are a bit too quick to dismiss minor differences - but if the difference is below the threshold of hearing a musician isn't going to notice.
What I keep trying to say is that differences are there and are real and they are improtant to musicians, but it is the attribution to material that may be wrong. Musicians just assume a difference is down to the thing they can see - a material difference is obvious in either ebonite or metal. And it's obvious in black lacquer or silver plate which are considered by some to soudn different to brass.

If the effect is either none or insignificant then I doubt it is significant. I don't think that is vast.
Where people think there is a difference they claim it to be a vast difference. Ligatures will be said to make a huge difference. You can get a difference if you don't tighten your ligature properly, but I think any difference in ligatures is subtle, and only a potential for difference, i.e. not a given.

In mouthpieces I'm not convinced 100% that there is no difference, but in all the tests I know of people can't identify different materials. They can with tap tests of different metals. That leaves the conclusion that material differences in woodwinds are, at best, very small.
 

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Because the amplitude if the vibration in relation to that of the air column at that point is much greater. Also because it may be enough to affect functional mouthpiece chamber size (recall that reed compliance is included in chamber size, if there is also "beak compliance" it must also be included) which will affect the sound directly.
An alto is about 1000mm long producing a wavelenth equivalent to 4000mm with a bell opening of around 80mm. Mouthpiece material vibrations will be in the order of around 0.001mm. The body may vibrate nearer 0.005mm, so how is the mouthpiece amplitude more?
 

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Did Backus actually say that the mouthpiece will not vibrate unless the reed hits the tip?
I don't think so. (Sax Piece mentioned the rails and the reed always is in contact with the rails. The tip is hit at higher volumes IIRC and it was interested in Pete Thomas's second test that the mouthpieces were hard to identify when that test was done playing very loudly.)
He does say how the air stream generates the standing wave. (Acoustic Foundations in Music. p218) and how the reed moving like a valve so that high and low pressure pulses set the air column in motion (p226)
 

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Basically it says the reed vibration cycle is cause by the air pressure in side being lower than that outside. As the air pressure inside the instrument starts off the same, in order for it to be lower than that outside, air would actually need to be sucked out of the mouthpiece, not merely blown in to it via a tiny hole.
Do you have the Backus book? (Acoustic Foundations in Music. p218)
 

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I'd go for what Benade says, whatever that is, ro whatever is in the University of NSW site.
Both very reliable authorities.
You seem to be suggesting Dr Murray Campbell and Dr Clive Greated arent' reliable sources? I don't think what they say differs from the two you mention. It's just the way it is explained that differs.
 

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Scargo said "I may be wrong, but the illustrations in the referenced page in Oric Muso's post actually seem the opposite (although they would serve adequately enough for a basic understanding)."

My thoughts, exactly. The illustration is out of phase and is useful only as an over simplification of what's happening. Unfortunately, as with many examples, the simplification comes back to haunt us. Blowing into the mouthpiece causes lower pressure inside the mouthpiece than outside. That has to be the case in order for the reed to close. Once closed, the pressure bounces back. Even though there is still pressure above ambient outside the reed (as the player keeps blowing), the pressure bounce back against the closed reed is high enough to open the reed against that pressure. Low when open, high when closed; exactly opposite of the illustration. It reminds me if the illustrations that use "sound arrows" to show how sound bounces around and out the end of the instrument. Another illustration that can do more harm than good by over simplifying a complex issue.
If you look at how the air column oscillates you'll see the air flow isn't like water through a hose. Blowing air in causes high pressure in the mouthpiece as the air isn't going straight through. When the reed is closed there is more pressure on it than in the mouthpeice. So the diagram might seem wrong, but it isn't.
 

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That's where we disagree. If there is high pressure inside the mouthpiece, what causes the reed to close?
The Bernoulli effect. More air goes in the open mouthpiece which means there's then less pressure in the mouthpiece than outside and the reed gets sucked back.

It's not like water in a hose (as the diagram assumes) because the mouthpiece causes the Bernoulli effect. The pressure differences would cycle through higher, lower, and neutral out of phase with the exact opening and closing of the reed tip. That's why I think that the diagram is as much of a hindrance as a help.
Read the text. It explains all this. If you read the Backus it says basically the same thing.

Why does high pressure in the mouthpiece cause the reed to close, as shown in the diagram?
Consider the system without the air stream. If the pressure is higher in the mouthpiece it'll force the reed open. If it is lower it'll allow the reed to close. It isn't the high pressure closing the reed. The diagram shows high pressure in the mouthpiece with the reed open. With a more open aperture, more air goes in. The air flow causes a Bernoulli effect which closes the reed.
 
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