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DonLeister

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Dean, I think you missed something if you're still including sound in the problem. The only issue I'm talking about is wood. If you're suggesting, as Wm is above, that the wood is different but the cause may not be treatment, maybe you should come out and say so? Or are still disputing that the wood is different?

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Dean, I think you missed something if you're still including sound in the problem. The only issue I'm talking about is wood. If you're suggesting, as Wm is above, that the wood is different but the cause may not be treatment, maybe you should come out and say so? Or are still disputing that the wood is different?

Of course I think the wood is different now. Just about anything made 300 years ago will undergo physical changes...especially when exposed to oxidation, handling etc...

The statement you supported was that the wood was treated 300 years ago but then again your posts seem to get edited so I don't know where you stand now.

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Of course I think the wood is different now. Just about anything made 300 years ago will undergo physical changes...especially when exposed to oxidation, handling etc...

The statement you supported was that the wood was treated 300 years ago but then again your posts seem to get edited so I don't know where you stand now.

I don't think I've done any editing in this thread that's changed the meaning of what I said. I personally believe the wood was treated somehow, but I was only challenging your desire for proof that the wood was different, and it appeared to me, and still did until that last post, that you were not blaming age, but rather challenging the observations.

Anyway, if that's what bothers you, it should be a snap to test. There's certainly no shortage of wood of that era in non-Cremonese violins to take a look at, but I still think it should be clear even to the eyes that Cremonese wood is different from the rest. If it's simply age, well, then French, German, and English violins from the same time were all exposed to dust mites, rosin, dirt, whatever you want to look at, so they should be the same as the Cremonese, if you're right.

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.... but I still think it should be clear even to the eyes that Cremonese wood is different from the rest.

Should it? I've noticed a visual difference in the presence of coatings, not in the wood itself.

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Certainly there's room for a difference of opinion, but I've see the insides of grafts and of edges getting doubled that were pretty far away from the coatings.

Dean, I'm inherently skeptical of age as a great equalizer in violin making, since there are tons of old violins from other schools and countries that show what age can't do.

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I am on the wood treatment camp for some 20 years, but I am still quietly doing my homework.

I too am doing my homework, but I don't see the need to join any camp when it comes to what the Cremonese did or did not do to their wood. I'll remain a "treatgnostic" for now... the evidence is not beyond doubt, and the bottom line is that it's not all that important to me what they actually did, anyway.

What IS important to me is what works, and I have plenty of reason to believe that treatments can improve acoustic performance. Thus the homework.

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Bruce, any thoughts on what would happen to wood after being exhaled on for many years?

I don't think what we exhale would affect the wood much. Sweat may be a real concern (chin rest was only invented much later, right?).

I have looked up the NMR spectra of dried wood aged over hundreds of years. Supposedly at this stage a few percent of the hemicellulose have naturally degraded. There is no difference from natural wood in the NMR spectra; aging does not do much. Stradivari's mapl by NMR spectra just does not look like wood, much closer to paper in fact. I don't think surface treatment could have caused this much change, it was probably soaked in something. So the wood treatment I mean here is not just surface coating.

I am really skeptical of fungal treatments that degrade lignin from a theoretical perspective. Lignin is like the cement that holds cellulose fibers together. As the violin vibrates under high tension in different climate conditions, the wood fibers will fall apart internally if the lignocellulose complex is damaged. However, Stradivari and del Gesu plates show obvious lignin degradation. The only logical explanation is to add some kind of bonding agent to hold everything together. Fig 5 shows basically this: adding borate to chemically crosslink carbohydrates. The reality may be much more complicated, but a rough picture is emerging.

My earlier comments about the "supreme importance" of wood treatment were made half-jokingly to show that I don't think the varnish is the center of the violin universe (after writing 50 pages about it). Michael pointed out something critical here, wood treatments often produce very variable results. It is hard to control the flow of fluids between different wood cells. In turn the initial property of the wood could affect a lot of decisions downstream.

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Certainly there's room for a difference of opinion, but I've see the insides of grafts and of edges getting doubled that were pretty far away from the coatings.

I have seen these too. I one case I redoubled an entire Strad back. Not just the edges, but a patch was fitted to the entire back. In most cases, the wood looked, behaved, and cut like other old wood.

I've run across a few examples which seemed to be pretty degraded (not just Strads, but other fiddles too), but this seemed to track loosely with how much general wear and tear the violin had. That's one reason I was wondering if altered wood could be connected to something usage related.

It would be interesting to know more about the source of the samples tested, and to have a large number of samples from instruments in varying conditions.

I'm not taking a position on whether wood was treated or not, just sharing some observations.

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I have too. I one case I redoubled an entire Strad back. Not just the edges, but a patch was fitted to the entire back.

Really?

David, I have never heard of such a thing.

Could you explain what was done a bit further, please? Curiosity is eating me up...

Certainly it wasn't carved and chalk fit?

thanks, and sorry about it if this question is hijacking the thread,

ct

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Really?

David, I have never heard of such a thing.

Could you explain what was done a bit further, please? Curiosity is eating me up...

Certainly it wasn't carved and chalk fit?

Yes, it was. The back had been previously fitted with a very large chest patch, and was a patchwork of other ugly stuff. I don't know whether I'd do it that way again or not. It was a while ago, and I'd need to be reacquainted with what I had to work with to second-guess it. Sometimes, you're handed something pretty decrepit, and are asked to make a viable fiddle out of it.

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....... I one case I redoubled an entire Strad back. Not just the edges, but a patch was fitted to the entire back. In most cases, the wood looked, behaved, and cut like other old wood.

Did you save any of the shavings from the original parts of the back? If so, has anyone done any "scientific" evaluation of them? Thanks,

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I don't think what we exhale would affect the wood much.

Please expand on the scientific basis for this statement.

ps - I am not getting at you in particular; just trying to make the point that much of the confusion is related to imprecision in definitions, assumptions and imputations (statistical, not legal, meaning).

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Did you save any of the shavings from the original parts of the back? If so, has anyone done any "scientific" evaluation of them? Thanks,

Yes, shavings were saved, but they were all mixed together.... original wood plus the chest patch which was removed, and possibly some shavings from the new doubling. This sounds strange today, but saving any of it seemed like an afterthought at the time. It might just as easily have all gone in the trash. To be useful in analysis, one would need to figure out which shavings are which. Or maybe the analysis would yield that information.

I recall that one small plastic bag of shavings left the shop with someone who said he wanted to analyze them. Never heard back from him, and can't remember who he was. It wasn't Nagyvary. That's not a Nagyvary joke.

I also in no way mean to be dismissive of Bruce Tai's research. I was one of the people who encouraged him to publish. I have my observations, but he has analyzed the results of much more research, with a background to know the strengths and limitations of the various tests used.

And I will also be happy to reconsider my observations and conclusions if they should conflict with those who have done heavy work on many more Strads than I have, like Rene Morel, Hans Nebel (Wurlitzer guys), John Dilworth or Andrew Faifax (London Beare shop guys), or John Becker. Include Roger Hargrave.

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I have no formal training, its just speculation

My take on this is that we have "human emotion" mixed with propaganda, reality and forgotten history mixed with overlooked science.

Some questions I have are, besides Strad's, were other violins from that time frame analyzed...or are we looking at this "thing" through "strad colored glasses"?

I have a feeling that other period instruments were looked at we would find similarities in the "potential" for "treatment"...I would speculate that the treatment is "universal" and the treatment is prolonged exposure to UV and other trace forms of solar radiation. Strads, being cleverly marketed way back when, made them a popular choice long ago, this popularity lead to them being "played in" much more so then many other violins, and well they were excellent to begin with, so by being exercised regularly, the wood elasticity is always optimum, and coincidentally they are "out" being displayed and played regularly, thus being exposed to uv//solar rays regularly. I'm sure if we looked at "unhappy" strads, those being unplayed and protected in dark rooms

{ to stop the uv radiation}that these instruments would at first hearing, not sound too "Strad" like.

At an atomic level, when sunlight falls on an object, the high energy provided by this radiation excites electrons, in some cases causing them to be displaced from bonds between atoms, particularly in organic compounds. This process can cause material to deteriorate and colours to fade. Objects also heat up causing their materials to expand and contract, often at different rates to each other. The differential movement can lead to stress resulting in damage to the structure of rigid materials. They can also dry out, again causing differential movement as well as cracking and crazing of some surfaces.

Could this be what "the treatment" is, wood that has been simply changed by being "rusted" by uv radiation? The oxidation also effects the internal metal compounds in the wood. Any metal compound that exists in trace amounts, that are subject to decay via oxidization, will be effected. The dimension, in this case the thinness of the material will expedite exposure into the inner structure. I would speculate that one could examine "old" wood and not find the same similarities, I cannot think of many wooden objects that are as thin as violins. It is this internal deterioration that mimics treatment perhaps.

Related to Mr. Dartons statement about the varnish "being different"...Again I would attribute this to Uv exposure of a very well finished piece that has been taken care of over the years? I've only had one Strad in my hands for about 20 seconds, so I'm no Cremona expert

Drying oils used as the medium for oil varnishes, Like all but the most simple organic compounds, are formed of the long carbon-chain molecules known as polymers. When exposed to UV radiation in daylight, the long molecular chains become unstable and a variety of reactions take place including 'free radical chain reactions' and 'auto-oxidation'. As a result the drying oils 'polymerise' to a semi-solid state. They are also bleached by light and tend to increase in transparency over time. This is because the refractive index increases, becoming closer to that of the pigments.

I see no solid evidence one way or the other for treated or untreated, nor do I see any evidence that Strads are the most superior other than the fact that everyone says so and seems to want to argue about it.

so sayeth the Grand Poo'Bah....that Nagy' guy, he's the lord high of everything else.

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I don't think what we exhale would affect the wood much. Sweat may be a real concern (chin rest was only invented much later, right?).

I have looked up the NMR spectra of dried wood aged over hundreds of years. Supposedly at this stage a few percent of the hemicellulose have naturally degraded. There is no difference from natural wood in the NMR spectra; aging does not do much. Stradivari's mapl by NMR spectra just does not look like wood, much closer to paper in fact. I don't think surface treatment could have caused this much change, it was probably soaked in something. So the wood treatment I mean here is not just surface coating.

I am really skeptical of fungal treatments that degrade lignin from a theoretical perspective. Lignin is like the cement that holds cellulose fibers together. As the violin vibrates under high tension in different climate conditions, the wood fibers will fall apart internally if the lignocellulose complex is damaged. However, Stradivari and del Gesu plates show obvious lignin degradation. The only logical explanation is to add some kind of bonding agent to hold everything together. Fig 5 shows basically this: adding borate to chemically crosslink carbohydrates. The reality may be much more complicated, but a rough picture is emerging.

My earlier comments about the "supreme importance" of wood treatment were made half-jokingly to show that I don't think the varnish is the center of the violin universe (after writing 50 pages about it). Michael pointed out something critical here, wood treatments often produce very variable results. It is hard to control the flow of fluids between different wood cells. In turn the initial property of the wood could affect a lot of decisions downstream.

Playing the Devils advocate, 100 year old wood is not 300 year old wood. And what was the thickness of the material you looked at, was it 2 to 5 mill thick?

I feel that the woods dimension has much to do with its rate of speed of interior changes when speaking of radiation effects

edit: I see you wrote "hundreds" not hundred, still curious as to the sample dimensions

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Please expand on the scientific basis for this statement.

We exhale water vapor and carbon dioxide. These are chemically inert and don't degrade wood.

And it is not caused by UV. I can give many reasons. But the simplest argument is that UV does add minerals into the wood.

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In a few years I may hope to gain access to good analytical chemistry instruments and a very fine violin collection. Conducting some wood analysis may be a fun thing to do if it does not negatively impact my academic career B)

I have already been frowned upon by coworkers who saw me researching violins ~that's just the brutal reality of academia today

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We exhale water vapor and carbon dioxide. These are chemically inert and don't degrade wood.

And urea, ammonia, acetone, abnormally reactive oxygen compounds, and various other things depending on diet and state of health?

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And urea, ammonia, acetone, abnormally reactive oxygen compounds, and various other things depending on diet and state of health?

True, but these are in trace amounts and the varnish is a barrier. I still think sweat (accompanied by heat, microbes, and pressure) in the absence of the chin rest is much more likely to cause changes. Mass spectrometry has shown that everything our skin touched for just a second has lots of keratin contamination. My wooden chin rest has already changed colors after playing just <1000 hours. The summer in Italy is pretty hot without A/C.

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"And urea, ammonia, acetone, abnormally reactive oxygen compounds, and various other things depending on diet and state of health? "

Perhaps the buffalo chips he used in the campfire that warmed his plates up for gluing changed when his old cow died. The tempering/annealing that took place probably had a lot to do with how cold it was at the time of assembly.

Rick

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I have looked up the NMR spectra of dried wood aged over hundreds of years. Supposedly at this stage a few percent of the hemicellulose have naturally degraded. There is no difference from natural wood in the NMR spectra; aging does not do much. Stradivari's mapl by NMR spectra just does not look like wood, much closer to paper in fact.

Not knowing the capabilities of NMR, just how accurately can you tell hemicellulose content with that process?

And what is the difference between wood and paper, chemically speaking?

We exhale water vapor and carbon dioxide. These are chemically inert and don't degrade wood.

What about slow hydrolysis? I know that I can make hemicellulose degrade quite rapidly with water vapor at elevated temperature, and that same elevated temperature without water vapor does nothing.

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