CT scan from an untrained eye.

[CJones]

So I been reading a lot of old threads in my spare time waiting on the varnish to cure on my #2 and I came across this image in an old thread but the whole thread like 14 pages turns out to mostly be D Burgess among others completely trashing let’s call him some guy Though I did skip over whatever he said and read all the trashing. It was entertaining. To the point. I noticed that the Strad and GDG on the top plate are quite a bit thicker as compared to the center on the slope of the arch ff area. To my pitiful math skills. 46% wider on the strad treble 38.5% on the bass on the GDG 42.5% Full disclosure I measured these with hand calipers blown up on my phone. So it’s not greatly accurate or scientific. 1.0 mm rib shown as reference for measurements  so measurements are not accurate unless ribs are 1.0 at that spot  

So getting to the points. 
1. That’s a lot thicker in the ff area than I’ve ever heard recommend. I’ve used 2.8 -3.0 center to 3.2-3.3 in the ff area. According my awful math skills looking at the strad treble  if I was 3.0 center height I would be 4.38 in the ff area on the GDG I would be 4.275. Something seems off bad. 
 

2. edge thickness is quite a bit thicker on the back minus the stainer. I get taking off the top a lot can affect this but it’s +/-  more or less around 1 mm

3. The strad is much thinner on the base side of top. 
 

4. The arch area of the back of the stainer is crazy thin. 

5. How great do these particular violins sound? 

I guess the question is. Am I just really messing something up with my measuring? I barely passed algebra in high school.I’m finding it hard to believe that it’s almost twice as thick in the arch area of the top on the bottom two. 

[David Burgess]

1 hour ago, CJones said:

I came across this image in an old thread but the whole thread like 14 pages turns out to mostly be D Burgess among others completely trashing let’s call him zuger.(spelled backwards ) Who I hope is gone and will stay away from this one.

Which of us do you hope is gone?

[Andreas Preuss]

I find the curvatures of the archings more interesting to study.

 

[Violadamore]

8 hours ago, CJones said:

So I been reading a lot of old threads in my spare time waiting on the varnish to cure on my #2 and I came across this image in an old thread but the whole thread like 14 pages turns out to mostly be D Burgess among others completely trashing let’s call him REDACTED Who I hope is gone and will stay away from this one. Though I did skip over whatever he said and read all the trashing. It was entertaining. To the point. I noticed that the Strad and GDG on the top plate are quite a bit thicker as compared to the center on the slope of the arch ff area. To my pitiful math skills. 46% wider on the strad treble 38.5% on the bass on the GDG 42.5% Full disclosure I measured these with hand calipers blown up on my phone. So it’s not greatly accurate or scientific. 1.0 mm rib shown as reference for measurements  so measurements are not accurate unless ribs are 1.0 at that spot  

So getting to the points. 
1. That’s a lot thicker in the ff area than I’ve ever heard recommend. I’ve used 2.8 -3.0 center to 3.2-3.3 in the ff area. According my awful math skills looking at the strad treble  if I was 3.0 center height I would be 4.38 in the ff area on the GDG I would be 4.275. Something seems off bad. 
 

2. edge thickness is quite a bit thicker on the back minus the stainer. I get taking off the top a lot can affect this but it’s +/-  more or less around 1 mm

3. The strad is much thinner on the base side of top. 
 

4. The arch area of the back of the stainer is crazy thin. 

5. How great do these particular violins sound? 

I guess the question is. Am I just really messing something up with my measuring? I barely passed algebra in high school.I’m finding it hard to believe that it’s almost twice as thick in the arch area of the top on the bottom two. 

1. - 4.  Stainers are reputed to be magnificent chamber music violins, but Strads and GDG's overall are supposed to support any soloist's tricks you care to indulge in, while having the projection to reach people in the back of the balcony, once you're used to the quirks of a particular instrument.  You think that this might have some relation to the structural differences? 

5.  In this league, that all depends on the skills of the operator and the hearing of the listener, doesn't it? 

I also feel that the amount of the enclosed volume of air should be considered as part of the structure when analyzing its function.  

 

[lFred]

almost no lining on that Guarn?

[CJones]

Well it’s not you David. I think you’re great! I read every line of you trashing him.  I didn’t read his stuff. If David and Don don’t want to hear it I don’t either. I don’t want that crap getting stuck in my head. I might think it’s right. After all I’m maestronet and YouTube trained. When you don’t know you hope someone will tell you when it’s crap. Thank you David. While you may not tell a lot of secrets you don’t mind calling bull crap one bit on someone leading folk’s astray 

[CJones]

But to the question are they really that thick in the ff area? That’s a lot. Especially on the treble side of the strad. I do understand that apparently no one really builds stainer copies for a reason but also most  grad maps  I’ve seen on famous makers instruments.  (Ya know off maestronet )seem to not look this way.  Like 2.6 center and maybe 3.0 or 3.2 in the ff. That’s only half a mm or so. These are over 1.5. Seems like a lot. Excluding the stainer. 

[LCF]

2 hours ago, Andreas Preuss said:

I find the curvatures of the archings more interesting to study.

 

Yes.

There are complex differences between those three cross sections. For example GDG has smallest linings but a thick plate edge platform. The Strad and Stainer have stronger recurve, GDG has more of a barrel vault. 

It is probable also that the Stainer originally had a much smaller bass bar unlike that great modern plank it now has. Perhaps one reason they fell by the wayside as performance requirements changed is they didn't respond as well to 'modernisation'?

[LCF]

There's anorher question which I don't know the answer to; should you count thickness at right angles to the surface ie the normal, or should it be reckoned vertically?

Measuring it in the (surface) normal direction is what makers do, but the numerical value of that versus vertical measurement changes with the slope angle of the arching.

[CJones]

I apologize Dr Mark. Maybe I got caught up.  I guess I had just finished up reading 14 pages of him arguing with great makers and he would not stop. Thus 14 pages and no answers to the topic. I will revise my comments.  I am certainly am here to learn not to offend   

[CJones]

Ok Dr Mark. He’s now just that guy if you remove the name from your post. Again my apologies 

[SCorrea]

In the readings of 14 pages of back and forth between these peeps, I have a question.  Why focus on one individual, focus on the conversation.  The conversation had a LOT of goodness in it in the rebuttals posted by the community.  THATS why people like him are valuable.  They galvanize a community and a lot of basics agreed to by many are put forth.  I value that.  Everybody contributes to advancing the craft in this forum.  Some by being the poster child for incorrectness, some by being part of the learned community that covers him with truth bombs, and some by knowing when to keep their mouth shut and absorb the lesson(s)

As a quiet one, I thank you all

[CJones]

35 minutes ago, SCorrea said:

As a quiet one, I thank you all

I feel like you contradicted yourself. I asked these questions because I didn’t get much info from the 14 pages. I admitted and apologized and edited my posts. I was being hateful and acknowledged it. I’m not sure why you felt the need to say all this after the fact. You’re kinda acting like me now   

[SCorrea]

10 minutes ago, CJones said:

I feel like you contradicted yourself. I asked these questions because I didn’t get much info from the 14 pages. I admitted and apologized and edited my posts. I was being hateful and acknowledged it. I’m not sure why you felt the need to say all this after the fact. You’re kinda acting like me now   

 

[SCorrea]

No contradiction, just a suggestion that you go back and reread the first exchange.  From there, the distillation of a specific question or question set is very possible.  Take the exchange, boil it down, ask specific questions you can't derive the answers to and you will be amazed at the help that shows up.  I am always treated well by the guys and gals here because I try to be on point with my questions and respectful of their time..

 

[CJones]

That wasn’t helpful. The contradiction was you’re the quiet one but still needing to “help” me understand how to act. I apologized did I not? How are you helping with anything or at this point being polite of my time or all the people that are reading this now thinking I wish it would quit showing hot and just go away. Your post has nothing to do with my original question. Again to everyone else. I apologize 

[Don Noon]

Getting back to the original question...

I wouldn't put much faith in CT scan images where there is no assurance of the level of accuracy.  And certainly scaling thicknesses to some semi-arbitrary scale won't tell you anything more.  Much better to use actual graduation maps from reliable sources.  Looking at CT scans for general shape and concept might be useful, though.

In the area in question, immediately above the F holes, I don't think it's all that strange to see a thin center and thick at the edges.  For example, the Titian goes from 2.2 minimum in the center to 3.1.  I wouldn't obsess over this.

[CJones]

 

19 minutes ago, Don Noon said:

For example, the Titian goes from 2.2 minimum in the center to 3.1.  I wouldn't obsess over this.

Thanks Don! You’re always so helpful. I looked for footage of the strad or GDG being played and past a news channel showing a few seconds being played of the strad I didn’t find any footage. I thought that maybe these were some of the lesser desirables tonally. Maybe now this will go away. Im over it. 

[LCF]

1 hour ago, Don Noon said:

Getting back to the original question...

I wouldn't put much faith in CT scan images where there is no assurance of the level of accuracy. 

Near enough for brain surgery but not good enough for Stradivaris 

 

 

1 hour ago, Don Noon said:

In the area in question, immediately above the F holes, I don't think it's all that strange to see a thin center and thick at the edges.  For example, the Titian goes from 2.2 minimum in the center to 3.1.  I wouldn't obsess over this.

I don't know if its real but a suggestion has been made that as larger bass bars were installed the top was sometimes thinned in their general vicinity. One potential subtlety is that the Strad cross section is thicker on the treble side near the bridge, thinner on the bass. 

Edited May 11 by LCF
Spellink

[MikeC]

I wonder if thicker edges result from their construction method.  They closed the box and installed the purfling and final fluting of the edges on a closed box.  Leave the edges thicker so that you don't accidently go too thin.  I have wondered how do you control thickness of the plate around the edges if you're using that construction method, seems like you are kind of working blind in that area.  

[CJones]

Mike C I often wonder if tonal adjustments were how this was done. You know they had a general idea how the shape would be from training. Maybe even a templet guide to get close. Set up to play and then thin the channel or various spots untie they found the sound agreeable. Would thinning the perimeter as a whole not make the whole plate as a whole move more easily to some extent? I have no idea or expertise on this but I’m thinking a possibility that’s why Del Gesu ff’s are all over. Play trim play trim  repeat. I lengthened the ff’s on a vso I did a re-grad on years ago, got it sounding pretty good and couldn’t stop now it don’t. 
 

LCF I can see the bass bar as a reason. Trying to even the mass out from the larger bar but to my untrained eye which is very untrained. It seems thinnest between where the bridge feet would be. Thinner almost under the strings. Maybe this was where Castle came up with his theory for tone peculiarities. Though I didn’t put much stock in his ideas. It was an interesting read if you like a lot of banter. 

[LCF]

It's only the one slice so you don't get the whole picture even though it's a critical area. It's like looking at only one rib from a longboat. 

I would be thinking stiffness rather than mass. 

[Don Noon]

6 hours ago, CJones said:

I looked for footage of the strad or GDG being played and past a news channel showing a few seconds being played of the strad I didn’t find any footage.

https://www.strad3d.org/music.html

Kavakos seems to think the Willemotte is pretty good.  Titian and Plowden don't seem to have the same fame, but I can't say much beyon that. The latter two are smaller models.

5 hours ago, LCF said:

Near enough for brain surgery but not good enough for Stradivaris 

I wouldn't want to have surgery where the surgeon downloaded an image of my brain from the internet that was taken by someone else and tried to figure out where to cut by scaling it 

[CJones]

6 minutes ago, Don Noon said:

I wouldn't want to have surgery where the surgeon downloaded an image of my brain from the internet that was taken by someone else and tried to figure out where to cut by scaling it 

Especially if he was untrained ,using calipers, and blowing up the image on his I phone. It would probably be a whole lot cheaper though. 

[Marty Kasprzyk]

2 hours ago, MikeC said:

I wonder if thicker edges result from their construction method.  They closed the box and installed the purfling and final fluting of the edges on a closed box.  Leave the edges thicker so that you don't accidently go too thin.  I have wondered how do you control thickness of the plate around the edges if you're using that construction method, seems like you are kind of working blind in that area.  

Anders Buen studied the acoustic effects of the different thickness profiles of Strad and DG violins.  Attached is his paper.

On_corelations_of_geometry_and_long_time_average_spectra_of_old_shortened.pdf