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[David Burgess]

So, how do your instruments sound?

[Don Noon]

So, how do your instruments sound?

 

While this may be interesting, a great sound (whatever that is) would not prove the theories behind the construction.  It would only prove that the theory/process does not cause instant death to the sound.

 

I haven't been around all that much, but I certainly have come across makers with a variety of ideas which seem fairly strange, yet produce very good sounding fiddles.  So, while I find Mr. Zuger's concepts are far from my own understanding of structures and acoustics, a good result by either of us would not prove anything about our theories.  Proofs would come from careful researchy-type testing, specifically designed to show the physics at work.  

[David Burgess]

Do we know how the physics of violin sound work?

 

I thought the proof was still in the pudding, and not determined by measurements or analysis.

[Torbjörn Zethelius]

Violin sound is in the metaphysics realm.

[Don Noon]

Yes, the proof of a good violin is in playing and listening to it.

 

My point is that you can come up with a wide variety of ideas that can be passed off as "scientific", make a violin according to those ideas, and come out with a decent instrument.  That does not prove that the result is due to the idea behind it.  

 

Proving ideas in the physics realm would be more focused and measurable, and not necessarily have anything to do with the perceived quality of the sound.  For example, if I wanted to prove that the structure vibrations were critically dependent on string tension, I could test that idea by measuring the mode frequencies at various string tensions.

 

Most of the competing construction theories somehow end up with a shape that is very close to a normal violin (Doug Martin and Marty excluded).  

[Johnmasters]

Dear Carl. It's a pity that you do not understand what's written in "The American Heritage"  This makes it even more difficult to understand what it means in practise.

Before a structure becomes dynamic it is forced mechanic and change shape by the string load top pitch. That process will take at least 24 hours. There are several investigations that show how the instrument change shape and where stress is produced. Stress and frequency are related to each other. A string must have a specific stress in order to vibrate with a specific frequency. Principally we find the same circumstances on the bout SHAPEs of the violin. They must hold enormous different stress condition in different direction on order to start vibrating spontaneous by the action of the string acting on the bridge and the structure underneath. Changing the thickness graduation on the bout at a specific Place Changes the stress condition and with this the location where a specific frequency earlier started spontaneous

So what we have to consider is, Arching shape, Wood condition thickness graduation, structural deflecting and stress condition, the dynamic behaviour of all this and finally the acoustic result.

Most scientist start studying the acoustic result and hope to find out what the structure would be becoming better. I did the other way around, thus started making a structure and then study the function as described above and finally the acoustic outcome. Hope you are able to understand the consequences of all this. You may study my internet site at www.zuger.se. and find your own understanding. Not agreeing just make a not for discussion. You will find my email address.

I have been wondering for years about the interaction of static loads with the dynamics of a violin. To first order, there should be none. They are clearly there however. I am presently interested to know if a geometric shape, when under static loads, could have a restoring force (in the dynamic motion) that is not symmetrical either side of neutral.

I mean for vibrations larger than "small." I realize that in the limit of small vibrations this coupling should be zero. But it seems that we have to go to a better approximation. What can you say about this?

I am doing FEA experiments now to see if static deformations could be on the order of the amplitude of a vibration caused by a bow. Do you know or have a view on this?

I would like to know some relative numbers. If a forced vibration is much smaller in amplitude than the deformation under loads, than I cannot see how static loads can effect tone.

But you may have some ideas ..... I understand what you are saying because I am also curious.

By the way, I was in some discussions a couple of weeks ago. I was never able to make my questions clear to the forum members. Good luck discussing with them. But you can talk to me, and be specific.

One thing is in question. Your example of the string makes me think of this.. Restoring forces in a violin plate could be effected by in-plane stresses. But how much? And how great is this contribution compared to the stiffness and shape of the wood? That has to be looked at to see if a plausible theory can be found.

[Johnmasters]

While this may be interesting, a great sound (whatever that is) would not prove the theories behind the construction.  It would only prove that the theory/process does not cause instant death to the sound.

 

I haven't been around all that much, but I certainly have come across makers with a variety of ideas which seem fairly strange, yet produce very good sounding fiddles.  So, while I find Mr. Zuger's concepts are far from my own understanding of structures and acoustics, a good result by either of us would not prove anything about our theories.  Proofs would come from careful researchy-type testing, specifically designed to show the physics at work.

His language is a little difficult. But he is suggesting the sort of thing that concerns me. You know that the normal modes of an axially loaded beam depend on the axial load. The question is how much. And is there anything here that can related to a violin.

Again, he is probably interested in the way I am. I said before that there may be an optimal shape which could be found by doing such and such. Nobody was able to follow what I said, and perhaps I was a little vague. I am willing to talk to this person.

At this time, I have made an FEA model of a dome with a radial contour of a curtate cycloid. It took some time to relearn all the requirements for working in the ABAQUS program.. but it is my main interest at this time.I am re-learning about output files and will be able to (perhaps) learn about normal modes of such a come as the perimeter is compressed inward.

No it is not a violin, but maybe I can get some idea of the size of any deforming force that may effect the normal modes frequencies.

You may have mentioned this before, but have you found any shifts of normal modes in a strung-up violin vs one that is relaxed? (with the soundpost in place)

[David Burgess]

Yes, the proof of a good violin is in playing and listening to it.

 

My point is that you can come up with a wide variety of ideas that can be passed off as "scientific", make a violin according to those ideas, and come out with a decent instrument.  That does not prove that the result is due to the idea behind it.  

 

I guess my point was that if a particular theory or set of theories produces instruments that don't sound decent, there might be more productive places to look. Cut to the chase, or look for lower-hanging fruit.

 

Unless the interest is purely academic.

[Johnmasters]

I guess my point was that if a particular theory or set of theories produces an instrument that doesn't sound decent, there might be more productive places to look.

 

Unless the interest is purely academic.

It has to be academic for a first look-see. In my case, because I need a simpler model to see if I can FIND a coupling of static loads to the normal modes.

I am wanting to see if there is a coupling whether it is good or bad for sound to the ear and mind. First step is to see if the idea has any merit AT ALL.

We all know something is going on after stringing up a violin. A first approximation would say that there should be no coupling of static loads to anything dynamic in the vibrations, driven or passive (normal modes/tap tones).

I said I would report, and I still intend to, even if I find nothing. But this IS a very interesting question and it could lead to some ideas that might help visualize what may be happening to a violin under stress.

My feeling is that the academic experiment to show there should be SOME interaction of loads to dynamics would at least suggest more questions. If you are interested only if a certain experiment will lead to a better tone, you are not looking to see what was really there. So I am saying that an understanding has to come first. Then decide if that IS the reason a violin sounds better or wrose.

[Carl Stross]

Dear Carl. It's a pity that you do not understand what's written in "The American Heritage"  This makes it even more difficult to understand what it means in practise.

Before a structure becomes dynamic it is forced mechanic and change shape by the string load top pitch. That process will take at least 24 hours. There are several investigations that show how the instrument change shape and where stress is produced. Stress and frequency are related to each other. A string must have a specific stress in order to vibrate with a specific frequency. Principally we find the same circumstances on the bout SHAPEs of the violin. They must hold enormous different stress condition in different direction on order to start vibrating spontaneous by the action of the string acting on the bridge and the structure underneath. Changing the thickness graduation on the bout at a specific Place Changes the stress condition and with this the location where a specific frequency earlier started spontaneous

So what we have to consider is, Arching shape, Wood condition thickness graduation, structural deflecting and stress condition, the dynamic behaviour of all this and finally the acoustic result.

Most scientist start studying the acoustic result and hope to find out what the structure would be becoming better. I did the other way around, thus started making a structure and then study the function as described above and finally the acoustic outcome. Hope you are able to understand the consequences of all this. You may study my internet site at www.zuger.se. and find your own understanding. Not agreeing just make a not for discussion. You will find my email address.

 

I never heard of "The American Heritage" textbook - I suppose it is a book on the acoustics of the violin. I don't know if I would understand it or not. I suggest ( again ) you start a new thread and explain your way of thinking about the working and bettering of violins. I shall read with interest and I am sure quite a few of our members will ask questions, contribute and debate. Usually, I am staying away from discussions about how violins work. We know how they work : they beat the air and make it move. 

[Johnmasters]

I never heard of "The American Heritage" textbook - I suppose it is a book on the acoustics of the violin. I don't know know if I would understand it or not. I suggest ( again ) you start a new thread and explain your way of thinking about the working and bettering of violins. I shall read with interest and I am sure quite a few of our members will ask questions, contribute and debate. Usually, I am staying away from discussions about how violins work. We know how they work : they beat the air and make it move. 

I think he misread the publisher's brand as part of the title. His english is not good, and he may be translating out of a dictionary. This is sad for me, because IF he is an engineer or physics person, he may be able to suggest some interesting things. But I will have a problem to talk to him with the language as it is.

[Carl Stross]

1. Do we know how the physics of violin sound work?

 

2. I thought the proof was still in the pudding, and not determined by measurements or analysis.

 

1. Nope.

 

2. Indeed, pudding is all that matters. I heard or read theories on how to improve a certain aspect of a violin but

I have never heard one on the "beautification" of the tone. We can't articulate what it means and definitely we can't

translate it into "equations". Great tone is still a matter of opinion and fashion.

[reguz]

Hi Johnmaster and others, "the American Heritage " is a Dictionary.(AMERICAN) Read about what I have written.  Anything wrong with that language?

For more information read my study of arching shape and function on www.zuger.se. READ IT ALL Before critisize any!!

[reguz]

Hi JohnMasters

send me your email and I will send you some written discussion I had with prof C Gough, concerning these questions,  .

You find my mail on my internet site.

[Johnmasters]

1. Nope.

 

2. Indeed, pudding is all that matters. I heard or read theories on how to improve a certain aspect of a violin but

I have never heard one on the "beautification" of the tone. We can't articulate what it means and definitely we can't

translate it into "equations". Great tone is still a matter of opinion and fashion.

You are right about some of this. But the issue of any possible effects of static loads on dynamics would be very nice to know about. For example, is there something that causes a "ceiling" on the output of a violin?

Some violins sound good a low volumes but won't seem to deliver more no matter how one tries. I realize one needs to look at the slip-stick action of the bow, but is this it? I think there is more.

Any understanding might be hard to incorporate for a maker. That does not mean it is not worth knowing.

[Carl Stross]

1. Hi Johnmaster and others, "the American Heritage " is a Dictionary.(AMERICAN) Read about what I have written.  Anything wrong with that language?

 

2. For more information read my study of arching shape and function on www.zuger.se. READ IT ALL Before critisize any!!

 

1. Could you supply a link to what you have written ? The Dictionary is here https://www.ahdictionary.com  but I don't seem to find your article.

 

2. I read your "study of arching shape and function" years ago. 

 

This is a Forum ( if you haven't noticed ). Start a thread, present your theory and interact with the members. We'll read with interest.

[Johnmasters]

1. Could you supply a link to what you have written ? The Dictionary is here https://www.ahdictionary.com  but I don't seem to find your article.

 

2. I read your "study of arching shape and function" years ago. 

 

This is a Forum ( if you haven't noticed ). Start a thread, present your theory and interact with the members. We'll read with interest.

1. Could you supply a link to what you have written ? The Dictionary is here https://www.ahdictionary.com  but I don't seem to find your article.

 

2. I read your "study of arching shape and function" years ago. 

 

This is a Forum ( if you haven't noticed ). Start a thread, present your theory and interact with the members. We'll read with interest.

I read it too. There were too many fudgings in the shape drawings. It seemed to be a way of making the upper and lower bouts similar in shape in the arching. I do not think this is too relevant. I want to know WHY the arching is such and so. Also how to place the inflections around the perimeter.

[Johnmasters]

Hi JohnMasters

send me your email and I will send you some written discussion I had with prof C Gough, concerning these questions,  .

You find my mail on my internet site.

I sent you a private IM. I did not find your email address. Mine is ........ jmluthier10@yahoo.com Please respond.

[Carl Stross]

You are right about some of this. But the issue of any possible effects of static loads on dynamics would be very nice to know about. For example, is there something that causes a "ceiling" on the output of a violin?

Some violins sound good a low volumes but won't seem to deliver more no matter how one tries. I realize one needs to look at the slip-stick action of the bow, but is this it? I think there is more.

Any understanding might be hard to incorporate for a maker. That does not mean it is not worth knowing.

 

Those all sound like interesting projects. 

[Johnmasters]

Those all sound like interesting projects.

Yes, I think so. In the previous discussions there was a bit of heat. I have simplified my testing objectives for the start of all of this. The one thing we cannot ignore is that tension of soundpost seems to affect sound. Also there is a "settling down" period for a newly strung up violin. Or the recovery of an old violin that has sat for a time unstrung.

I am firm in my view that anything of interest to a violin would be seen as a general case in other types of structures. Likely it is something well-known but has not been extended to the violin out of low interest. I would like to see what kinds of numbers are involved. (In order to see if there could be significant effects predicted for a violin.

At present, I am using an isotropic material in the dome model. But I have numbers for orthotropic spruce and maple. And I have previously run violin models with these materials. I did not have a good question to ask of the measurements however !! That was maybe 5 years ago, but at least I have a lot of models that Abaqus "says" are OK.

[Christopher Jacoby]

Hi Johnmaster and others, "the American Heritage " is a Dictionary.(AMERICAN) Read about what I have written.  Anything wrong with that language?

For more information read my study of arching shape and function on www.zuger.se. READ IT ALL Before critisize any!!

I had a pleasant daydream about some dictionaries falling off a shelf onto you just now. You might notice that your tone is very different from ANYONE else's on this thread. Go forth, and start thy own imperious thread, what say you?

[reguz]

HI All. I'm still wondering if there is a real interest by you to listen and probably learn some about what others have find out.

It seem already to be a problem Reading in a Dictionary after the meaning of some words, Acoustic, dynamic, static, mechanic interacting.

All these words have a place in expressing the behaviour of the violin structure.

More difficult to describe is interaction between structures but there is an easy structure anyone can test interacting.

You are able to check on a bow. If the interaction is at the utmost level the bending of the stick is almost equal to the elasticy of the bow hair. A dynamic condition arise when you smash the end of the stick in your open hand.

On the violin we also find interacting behaviour but that the stick is the strings and the bow hair the violin body.

Plying pizzicato show us by duration how long time the interaction is going on.

To find an optimal condition the bouts of the back end belly must interact optimal and this only can be achieved by carefully graduation on a strung instrument. This is done on the outside either b polishing the oxidized varnish or on the instrument in the White by scarping on the Surface. You the violin maker must listen to the frequency to improve., not by just playing the instrument. On tone on a string also is possible to play on Another string. If the tone ans amplitude are good on both you jhave made an improvement. This tone is able to check on ll four strings. This process can start after you have done Everything possible wth the location of the sound post and the quality and shape of the bridge. Has any of you tried to d this?

[Carl Stross]

HI All. I'm still wondering if there is a real interest by you to listen and probably learn some about what others have find out.

It seem already to be a problem Reading in a Dictionary after the meaning of some words, Acoustic, dynamic, static, mechanic interacting.

All these words have a place in expressing the behaviour of the violin structure.

More difficult to describe is interaction between structures but there is an easy structure anyone can test interacting.

You are able to check on a bow. If the interaction is at the utmost level the bending of the stick is almost equal to the elasticy of the bow hair. A dynamic condition arise when you smash the end of the stick in your open hand.

On the violin we also find interacting behaviour but that the stick is the strings and the bow hair the violin body.

Plying pizzicato show us by duration how long time the interaction is going on.

To find an optimal condition the bouts of the back end belly must interact optimal and this only can be achieved by carefully graduation on a strung instrument. This is done on the outside either b polishing the oxidized varnish or on the instrument in the White by scarping on the Surface. You the violin maker must listen to the frequency to improve., not by just playing the instrument. On tone on a string also is possible to play on Another string. If the tone ans amplitude are good on both you jhave made an improvement. This tone is able to check on ll four strings. This process can start after you have done Everything possible wth the location of the sound post and the quality and shape of the bridge. Has any of you tried to d this?

 

We are interested, why not START A NEW THREAD and present your theory ?