For Peter KG, Don Noon, and others interested in engineering.

[Addie]

David,

 

Stradivari was often required to produce sets of violins so I can understand that they should be similar in appearance. His use of forms allowed him to maintain strict control over the outlines but what about the critical archings? 

 

Maybe I'm wrong but I don't think arching templates have survived.

Might this suggest that some principle apart from templates was used to guide the arching?

As luthiers all know, if you want acoustic consistency, you must adapt arching and thickness to account for variations in wood.

 

Glenn

 

Hi, Glenn,

 

this image is from the Museo Stradivariano (back when it opened).

 

The templates were made by Guadagnini.

[curious1]

Hi, Glenn,

 

this image is from the Museo Stradivariano (back when it opened).

 

The templates were made by Guadagnini.

Are these not templates of existing instruments? As opposed to theoretical/ idealized archings. Aren't they labelled Nicolo Amati, Antonio Stradivari etc.

[GlennYorkPA]

Hi, Glenn,

 

this image is from the Museo Stradivariano (back when it opened).

 

The templates were made by Guadagnini.

 

Hi Addie,

Thanks for sharing.

The exhibition looked very different when I saw it a couple of years ago and I have no recollection of the arching templates so i suspect they were not part of Strad's legacy.

 

Glenn

[francoisdenis]

Francois,Thank you for your input,Sorry but I have a question,

Do you mean that the backs max height is often noted to be slightly lower than the top.?..or slightly lower than the ratio's would indicate? i.e. flatter. Also I assume the max height of most plates to be in the area of the stop or sound post,and that point A will be above ,(north of) that point .... following this method a fellow would figure from the Max height and NOT the height @ A point? The diffrence would be relitavely small but little details do make up the ensamble .

  I have noticed that when following my arching templates of the Plowden and Messie for shapping, upon compairision to your ratios,they apply remakably well, usualy within a few tenths of a mm. This leads me to think that you could be onto something.

 One more borring thought on Ratio's and work methods, When splitting wood it is VERY important to split down the center, or the split will vere to the weak side. 1st grade stuff, I realize..... a lifetime of splitting wood for violin tops ect. would produce a "ratio" tuned way of seeing or processing, be it thoughts or wood.  Another observation....the glass is always either half emty or half full ...it almost never has 3.145  cm cu of wine in it.

I'm saying that the reference measurement of all the ratios of the back will be the highest point of the arching of the back. likewise the reference measurement of all the ratios of the top will be the highest point of the arching of the top. Whatever is the value of this reference measurement and whatever is its position along the long arch. So this reference doesn't need to necessarily match the cross section of the two diagonals.

To say few words about the theoritical background of this approach. We all know that archings have suffered of distortions which let widely open the doors of the imagination about their interpretation. But, as somebody says, as they are measurements for every thing in the violin why archings would except this rule? Speaking of history, the Cremonese violin has inherited of two different building traditions. The muslim influence is visible in all details pertaining the luth tradition of making (nailled neck -bending sides..) in the other side the old christian tradition of the fiddle making remains in the  carving processes used for the archings. Gothic fiddles are basically a piece of carving which clearly used archings and all the details of their construction are known by the personages playing these instruments on the porches of the cathedrals.

That means that archings and instrument making are an old story furthermore evidently connected with gothic technics. Speaking of the archings the gothic approach of vaulting is the cross, speaking of carving the 3 points compass is an old tool used to reproduce any form and measures. So I assume that the two processes could have been combine. It's is what i have experimented for many years with some succes I guess.

For those that could be curious to do their one experimentation this Strad paper can be downloaded on my web site (www.francoisdenis.com). You know that the Strad standard is quite restrictive so this article is only a short exposure of a large field of researches. Other patterns than the simple cross existed and can be used as well for ratios. 

So you have to consider that the example of the paper is only one possibilities among many others...may be not the best one ....

[Torbjörn Zethelius]

That means that archings and instrument making are an old story furthermore evidently connected with gothic technics. Speaking of the archings the gothic approach of vaulting is the cross,

Hi Francois, that's right. The cross in the arching is inspired by the technique of cross vaults in gothic cathedrals.

Best, Torbjörn

[Torbjörn Zethelius]

It works making arches or making violins that sound great?

Yes.

[Torbjörn Zethelius]

Yes, and maybe some metrics to prove that they actually match "the various types of arching you see in Cremona".

This could be done with 3D CAD, though I'm not very good with that technology.

[actonern]

Torbjorn:

 

You get full marks for persistence!!!

[Torbjörn Zethelius]

Perhaps the physics is that the old arching is very close to catenary, which has special charateristics for arches and load bearing in a thin shape.  But the old arches are slightly flatter than a true catenary.  The emperical evidence in favor of finding and using the old method is the relative success of these instruments with the player/investor/collector/dealer communities.

I assume that you are talking about the outside shape. It may not have much to do with true catenaries, it's true. Also, working with a shadow and straight edge may not produce true catenaries. BTW Librum Segreti di Butthega talks about the inside vault focusing the sound, which would point toward the ideal being a parabolic curve. However, a parabolic shape can be approximated very closely using a chain as Galileo Galilei has stated. The catenary deviates from the parabola as it gets deeper, but the violin has shallow curves so the chain works well for this purpose.

[John Masters]

I assume that you are talking about the outside shape. It may not have much to do with true catenaries, it's true. Also, working with a shadow and straight edge may not produce true catenaries. BTW Librum Segreti di Butthega talks about the inside vault focusing the sound, which would point toward the ideal being a parabolic curve. However, a parabolic shape can be approximated very closely using a chain as Galileo Galilei has stated. The catenary deviates from the parabola as it gets deeper, but the violin has shallow curves so the chain works well for this purpose.

Could you discuss the rounding off of the concave curve to give the recurve?  And then the gradations determine the external shape of the recurve?

[GlennYorkPA]

Could you discuss the rounding off of the concave curve to give the recurve?  And then the gradations determine the external shape of the recurve?

 

Catenary curves have been discussed ad nauseam in this forum and there is little new to say. 

More importantly, they seem not important as classic plates with post patches, cleats, bulges and other types of plate distorsions continue to perform like classic plates. 

The new idea is that the channel round the edge, sometimes used for voicing the plates, has a much greater bearing on performance.

 

Glenn

[Torbjörn Zethelius]

Could you discuss the rounding off of the concave curve to give the recurve?  And then the gradations determine the external shape of the recurve?

Hi John, Firstly, my apology for "hijacking" this thread. Every time I mention my inside first method, I get criticized and must explain/defend myself for it, it seems.

The rounding off is done at the very last stage when I scrape the plate smooth. I may use a small plane first in some areas, but a sharp scraper should do it equally well. It's not really much that's taken off. I just want a nice curve instead of a sharp edge. Also, the roundness prevents the thickness punch to accidentally make deep holes on the outside in that area. On the outside, I finish the recurve channel to a pleasing shape for my eyes. The box is closed at this stage so I don't even know the final thickness of the recurve area. But I assume that it will be somewhat thicker than what I graduate the plate to. Or conversely, if I decide to make a thicker plate for some reason, it may end up thinner. I just don't know, and I don't care. From experience I know that it doesn't matter that much, the thickness, as long as I'm not doing something very extreme; which I don't. Usually, I follow Sacconi's graduations. more or less. Lately, however, I've been experimenting with thicker graduations á la Del Gesu. From our collective experience, we know that it can work. So I'm doing it.

 

I don't consider this part of the arch to be of much importance for the sound, but rather a visual aspect. As I've said, it works for me.

 

The external shape is a result of the graduations that I give the plate, and the manner in which I finish the edge. As a general rule, I think it's a good idea to follow Sacconi's explanation on how to finish the edge, and from studying the original Cremonese instruments by all the makers for a general understanding of how Cremonese edgework was done. Roger Hargraves writings is also a good source for information. My aim is not to copy, but rather to understand and find my own style within the Cremonese fashion. I hope this answers your question.

 

I guess I should add that if I were to make a wide outside recurve, as I did in the article, the edge on the inside would have to be more rounded for a gentle curve. It should please the eye, that's the goal. An arch like that would be very close to curtate cycloids, while a tight recurve would result in less of that. A tight recurve means that I make the inside catenary come very close to the rib linings, so the rounding would be comparatively small.

[Torbjörn Zethelius]

Catenary curves have been discussed ad nauseam in this forum and there is little new to say. 

More importantly, they seem not important as classic plates with post patches, cleats, bulges and other types of plate distorsions continue to perform like classic plates. 

The new idea is that the channel round the edge, sometimes used for voicing the plates, has a much greater bearing on performance.

 

Glenn

Glenn, the cleats and patches may be the reason that some modern instruments outperform the old ones in blind tests. Just a thought. And for voicing the plates; I don't do that sort of thing. But don't let me discourage you from doing it, by all means.

[Carl Stross]

 Firstly, my apology for "hijacking" this thread. Every time I mention my inside first method, I get criticized and must explain/defend myself for it, it seems.

 

 

Absolutely no need to apologise, Torbjorn, You have a wonderfull method which shows fantastic insight and the courage to do things differently.

Please, one day, you might want to prepare for us a more detailed article or even a thread where we could follow your system.

[MikeC]

Hi, Glenn,

 

this image is from the Museo Stradivariano (back when it opened).

 

The templates were made by Guadagnini.

Some 'inside' arch templates in there?  

[MikeC]

Absolutely no need to apologise, Torbjorn, You have a wonderfull method which shows fantastic insight and the courage to do things differently.

Please, one day, you might want to prepare for us a more detailed article or even a thread where we could follow your system.

I was going to suggest a thread also and you beat me to it!     It would be interesting to see more details of the whole process.   There are some questions like how do you get the straight area on the long arch of the top plate?   And why does the anvil have padding to protect the inside from getting dents where they won't show anyway?   And how do you get rid of all the dimples on the outside of the plate?  

 

When I built my first VSO I used a punch to get an even depth on the purfling channel (I was clueless lol ).   After carving the channel, I stained the wood and some of the pits that I thought were gone suddenly reappeared!   Of course I would not stain like that again,  beginner mistake. 

[GlennYorkPA]

Glenn, the cleats and patches may be the reason that some modern instruments outperform the old ones in blind tests. Just a thought. And for voicing the plates; I don't do that sort of thing. But don't let me discourage you from doing it, by all means.

 

Torbjorn,

Thanks for your comment.

I haven't made a violin in over 30 years;  I just collect and play them.

So I'm interested in the relationship between the making process and the performance because I'm detached from it.

I'm fascinated that you attach no acoustic significance to the recurve preferring to concentrate on the arching.

I thought John did a good job drawing attention to this detail and it deserves more discussion.

 

I have had several modern violins from Italian luthiers (they are readily available in the auctions rooms at modest prices) and none of them stands the test of time. Even beat up 18thC violins generally outperform them so I'm persuaded that all the attention paid by many modern violin makers to arching (and it seems something of an obsession) doesn't capture what some old instruments deliver.

 

I don't want to fall into the trap of generalizing because I know that some moderns perform well but, let's face it, most are mediocre and succeed in thrilling for a while and then are consigned to the closet or the sale room. (Yours may well be the exception   ).

 

Earlier in this thread, mention was made of a shallower channel in the block area of Cremonese violins. That got my attention because it sounds like a significant detail of the arching that may have been overlooked. But the discussion lapsed back to cycloids and catenaries where differences of fractions of millimeters between theoretical shapes and chiselled copies are discussed as though they held a crucial key to performance characteristics which they demonstrably do not.

 

From a performer's point of view, what distinguishes most modern violins from the million dollar+ instruments isn't the tone (harmonic spectral analysis) it's the ease of tone production. Ask any great performer and they will acknowledge that they commission and own modern violins to give their Strads and DGs a rest but they are exhausted after performing a concerto on them. The oldies play themselves and that's a quality I don't see discussed much. 

 

Glenn

[Marty Kasprzyk]

Torbjorn,

Thanks for your comment.

I haven't made a violin in over 30 years;  I just collect and play them.

So I'm interested in the relationship between the making process and the performance because I'm detached from it.

I'm fascinated that you attach no acoustic significance to the recurve preferring to concentrate on the arching.

I thought John did a good job drawing attention to this detail and it deserves more discussion.

 

I have had several modern violins from Italian luthiers (they are readily available in the auctions rooms at modest prices) and none of them stands the test of time. Even beat up 18thC violins generally outperform them so I'm persuaded that all the attention paid by many modern violin makers to arching (and it seems something of an obsession) doesn't capture what some old instruments deliver.

 

I don't want to fall into the trap of generalizing because I know that some moderns perform well but, let's face it, most are mediocre and succeed in thrilling for a while and then are consigned to the closet or the sale room. (Yours may well be the exception   ).

 

From a performer's point of view, what distinguishes most modern violins from the million dollar+ instruments isn't the tone (harmonic spectral analysis) it's the ease of tone production. Ask any great performer and they will acknowledge that they commission and own modern violins to give their Strads and DGs a rest but they are exhausted after performing a concerto on them. The oldies play themselves and that's a quality I don't see discussed much. 

 

Glenn

[Marty Kasprzyk]

What does that mean "ease of tone production"?

 

It it from a slow bow speed and/or low bow downward force?

[GlennYorkPA]

What does that mean "ease of tone production"?

 

It it from a slow bow speed and/or low bow downward force?

 

Oh, it means the string crackles into life as soon as the bow touches it. 

Most violins can be made to produce a reasonable sound but they require work which is tiring.

 

I suppose I mean greater bow pressure and faster speed but the result is that one tires after a while due to constant muscular tension. The good violins seem to encourage relaxation and yet respond more readily.

 

It's like riding a thoroughbred rather than an old mare. They both get you there they the journey is easier and more enjoyable on the one rather than the other.

 

Glenn

[Carl Stross]

Oh, it means the string crackles into life as soon as the bow touches it. 

Most violins can be made to produce a reasonable sound but they require work which is tiring.

 

I suppose I mean greater bow pressure and faster speed but the result is that one tires after a while due to constant muscular tension. The good violins seem to encourage relaxation and yet respond more readily.

 

It's like riding a thoroughbred rather than an old mare. They both get you there they the journey is easier and more enjoyable on the one rather than the other.

 

Glenn

 

I can't quite get what you're talking about here but being past middle age, I'll take the old mare anytime. I find thoroughbreads to be costly and lacking focus.

[GlennYorkPA]

I can't quite get what you're talking about here but being past middle age, I'll take the old mare anytime. I find thoroughbreads to be costly and lacking focus.

 

Really? You don't understand what I'm talking about? It's not my private observation.

 

See Evan Smith post #31:  

"I see this thinking exhibited strongly in strad arching,,,

not so much in other makers,

 

If the inflections are positioned in the right places, the instrument will have a higher sensitivity to the attack of the bow."

 

Glenn

[Carl Stross]

Really? You don't understand what I'm talking about? It's not my private observation.

 

See Evan Smith post #31:  

"I see this thinking exhibited strongly in strad arching,,,

not so much in other makers,

 

If the inflections are positioned in the right places, the instrument will have a higher sensitivity to the attack of the bow."

 

Glenn

 

 

Sorry ! Just read it now. Quite clear.

[GlennYorkPA]

Sorry ! Just read it now. Quite clear.

Have you noticed this difference in playability between violins?

[Carl Stross]

Have you noticed this difference in playability between violins?

 

Yes. Absolutely. I heavn't played for some 30 years though and at the time I wasn't informed enough to attribute the differences to construction issues. To me it was more a matter of bridge / post fit.