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I started measuring density and moisture content of my materials 44 years ago, but that didn’t tell me if it was the best wood. Choosing wood by instinct or based on esthetics is not a sufficiently satisfactory solution. Like many violin makers, I made quite a few mistakes in my youth; nevertheless, I ended up understanding empirically which wood was the most favorable for making violins, but not the best.

 

I have had a Lucchi elasticity tester for 30 years. Thanks to this device, I have learned how to recognize the true qualities of tonewood and how to eliminate certain materials, particularly those with insufficient transverse elasticity and celerity. The mode 2 frequency can drop as far as 45 Hz below its octave, even when you leave greater thickness at the center of the top or back plate.

 

Longitudinal celerity nearly always follows the curve representing longitudinal elasticity. Transverse elasticity and celerity can present aberrations, i.e., a lack of proportion with the wood’s other characteristics.

 

Calculating the ratio between longitudinal and transverse celerity allows you to predict what problems will occur in tuning the frequency of the extrados (multiple configurations of the nodal regions on top plates) and to better distribute the thicknesses for a given frequency.

 

 

N° 81 D 0.453  MC 9.2% Cl 5920 m/s Ct 1480 m/s  Cdi 4

 

N° 51 D 0.41 MC 12% Cl 5820 m/s Ct 1530 m/s Cdi 3.8

 

 

The celerity discrepancy index in plates  81 and 51 is too high: these two plates must be eliminated because they are impossible to tune (insufficient transverse celerity).

 

 

www.kreitpatrick.com

Edited by Patrick KREIT

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I started measuring density and moisture content of my materials 44 years ago, but that didn’t tell me if it was the best wood. Choosing wood by instinct or based on esthetics is not a sufficiently satisfactory solution. Like many violin makers, I made quite a few mistakes in my youth; nevertheless, I ended up understanding empirically which wood was the most favorable for making violins, but not the best.

I have had a Lucchi elasticity tester for 30 years. Thanks to this device, I have learned how to recognize the true qualities of tonewood and how to eliminate certain materials, particularly those with insufficient transverse elasticity and celerity. The mode 2 frequency can drop as far as 45 Hz below its octave, even when you leave greater thickness at the center of the top or back plate.

Longitudinal celerity nearly always follows the curve representing longitudinal elasticity. Transverse elasticity and celerity can present aberrations, i.e., a lack of proportion with the wood’s other characteristics.

Calculating the ratio between longitudinal and transverse celerity allows you to predict what problems will occur in tuning the frequency of the extrados (multiple configurations of the nodal regions on top plates) and to better distribute the thicknesses for a given frequency.

N° 81 D 0.453 MC 9.2% Cl 5920 m/s Ct 1480 m/s Cdi 4

N° 51 D 0.41 MC 12% Cl 5820 m/s Ct 1530 m/s Cdi 3.8

The celerity discrepancy index in plates 81 and 51 is too high: these two plates must be eliminated because they are impossible to tune (insufficient transverse celerity).

www.kreitpatrick.com

Peter, would you please use a modern English physics or engineering word instead of celerity. The only thing I could find about celerity is "swiftness of movement." (Archaic)

Do you mean perhaps the inverse of damping? Perhaps you mean speed of sound?

Thanks.

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You mean Patrick, because I would say "äänen nopeus". But I think celerity is a great word, that origins from middle French and Latin. http://www.dictionary.com/browse/celerity

 

And it's related to wave speed: http://encyclopedia2.thefreedictionary.com/wave+celerity

 

By definition speed of sound might be wrong, because is it "sound" anymore when pressure travels through another material than air?

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By definition speed of sound might be wrong, because is it "sound" anymore when pressure travels through another material than air?

 

Using your own reference source, speed of sound is used for wave speed in solids, liquids, and gasses. http://encyclopedia2.thefreedictionary.com/speed+of+sound

 

It is the term I have always heard for speed of a pressure wave, and never heard the term "celerity" until Patrick showed up with it.

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Using your own reference source, speed of sound is used for wave speed in solids, liquids, and gasses. http://encyclopedia2.thefreedictionary.com/speed+of+sound

It is the term I have always heard for speed of a pressure wave, and never heard the term "celerity" until Patrick showed up with it.

I find languages and culture very interesting. I have to use three languages all the time and I'm not good at any of them, not even my first language Swedish. I use to work with a French guy too and we actually had e-mail exchange today (in English, I have forgotten every French words I learned in school). His English has some similarities with Patrick's,a certain elegance in his phrasing. David B thought I was an American some times ago when I had picked up some phrases here on this forum. Just writing... Languages and culture they go hand in hand. Sometimes we are annoyed by other culture's speaking and writing. Personally I get often irritated by Finns, when I find them speaking and writing without saying absolutely nothing and total lack of elegance. But that's culture and me not understanding.

Celerity was new to me too and I found it interesting because I understood it without knowing the word. Generally I find Patrick's writing very educative, elegant and with an underlying sense of humor, again culture I think.

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3 hours ago, Peter K-G said:

This is the best I could do with this piece of wood. I really need to find a good wood supplier.

If .49 density is all you can get, I'd look for a new supplier too.

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If I had used this wood when I started making 20 years ago, it would have ended up ~90 g, so I'm quite satisfied with the results. The lowest I have used was 0.37 and I calculated it's about 40 cm3 more wood than this one. The best violin I have made, has a top of 0.47 density.

Don,

I had a good supplier (my friend who also makes violins), but he does not sell any of the great wood he has anymore. It's only for his own production. Ordering wood from various tonewood dealers on the Internet is a gamble, mostly lightweight firewood (in my opinion). Hope some tonewood dealer starts to measure density and speed of sound soon.

Progress today:

http://www.thestradsound.com/ongoing/progresstoday

 

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5 hours ago, Peter K-G said:

Hope some tonewood dealer starts to measure density and speed of sound soon.

I'm sure many have that information on a spot basis, but each piece can vary, and it's far too much effort to measure each one. So I can see why they normally don't advertise it.   I have heard of a supplier where you can specify what density you want, and they will measure and select... but it will cost you a bunch extra.  Simeon Chambers was one of the few that listed the approximate density.

I think it's up to you to pick and choose.  Most suppliers track by the log, so if you find a good set, then you can get more from that log. 

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1 hour ago, carl stross said:

Not ONE sound sample in SIX years. :)  When are we going to hear that blessed tone ?

Probably about the same time you finish your scrapwood violin.

 

1 hour ago, Peter K-G said:

Here is some Stradivari secrets, especially for you Don ;)

If it's a secret, you sure are bad at keeping secrets.  

I keep plenty of data secret, not because I want to keep valuable secrets to myself, but because I don't want to mislead anyone into thinking that it means anything.  And right now, most of it seems pretty meaningless.

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5 hours ago, carl stross said:

Well, I wasn't aware there is a connection...

Not a connection, just a common schedule :)

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2 minutes ago, Don Noon said:

Not a connection, just a common schedule :)

Well, that might be. Let's see : each with our specific interest, he's around No 5 and I'm around No. 50 ? And all of my guinea pigs are sold and in use. Some of them in heavy use. It's why I keep quiet - don't want to make David feel bad inside. :) You'll remember he chickened out of the competition. :)  He's welcomed back at any moment:lol: 

 

 

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17 hours ago, Don Noon said:

If it's a secret, you sure are bad at keeping secrets.  

I keep plenty of data secret, not because I want to keep valuable secrets to myself, but because I don't want to mislead anyone into thinking that it means anything.  And right now, most of it seems pretty meaningless.

Your engineering nature is impeccable, I say this with respect, even if I have a completely different approach to research.

 

 

(ps. Carl, you don't like Il Cannone or The Soil anyway so no point for me to post recordings, as mine sounds exactly like them)

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1 hour ago, Peter K-G said:

(ps. Carl, you don't like Il Cannone or The Soil anyway so no point for me to post recordings, as mine sounds exactly like them)

Who told you that ????  Peter, it's not about me, it's about you. After 6 years of threatening the whole MN with your magic method it's about time you bless us with some tone samples which if good, might make us true believers. If you are not interested in convincing us then what is the purpose of it all ??? Therapy ? ;) 

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19 hours ago, carl stross said:

Who told you that ????  

I don't follow what others tells me about what someone said, instead I listen to what you say directly and take your word for it.

 

 

Capture.JPG

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1 hour ago, Peter K-G said:

I don't follow what others tells me about what someone said, instead I listen to what you say directly and take your word for it.

 

I see - you are in therapy. But it isn't quite working. :lol:

You pasted on MN a sound sample ( which I remember perfectly ) with some hard to play, inflexible and erratic violin which you alluded later to have been the Canone.

I heard the Canone twice and once I heard it for a lengthy period of time and from all distances and all angles. It was a superb violin. I've no idea what was the thing you posted on MN but for sure it did not sound like how I knew Il Canone to sound under two different players live and a couple more, recorded.  And by the way, I played The Soil quite a bit.

Yourself and the other one :) trolled MN in hundreds of posts claiming to have a Golden Method which produces Strad like new instruments. You claim to be "Reproducing the Strad Sound". :):):) Most sane people were skeptical given that the method was nothing but the usual "tuning" with the added complication with tracking humidity. I remember David Burgess went as far as offering to do a controlled test of one of your  oeuvres and offered to pay all transport costs.  

Is it not high time you make good on your promises and give us a comprehensive sample of the reproduced Strad sound ? 

 

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I like sound clips! :D

1 hour ago, carl stross said:

...  And by the way, I played The Soil quite a bit....

Story? :)

Not in Peter's thread of course, but in a new one?

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1 hour ago, carl stross said:

You pasted on MN a sound sample ( which I remember perfectly ) with some hard to play, inflexible and erratic violin which you alluded later to have been the Canone.

Here is the particular sound clip of the bad sounding, inflexible and erratic violin we are talking about:

BadSoundingIlCannone.mp3

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