Music

Computed tomography used to recreate a Stradivarius violin

Computed tomography used to recreate a Stradivarius violin
Photograph comparing the original Stradivari Betts violin with the carved plate of the reproduction. (Photo: RSNA)
Photograph comparing the original Stradivari Betts violin with the carved plate of the reproduction. (Photo: RSNA)
View 17 Images
Photograph of the CNC machine carving the Betts violin reproduction. (Image: RSNA)
1/17
Photograph of the CNC machine carving the Betts violin reproduction. (Image: RSNA)
Photograph of the front and back of the original Stradivari Betts violin. (Image: RSNA)
2/17
Photograph of the front and back of the original Stradivari Betts violin. (Image: RSNA)
3/17
Photograph of the front of the original Stradivari Betts violin. (Photo: RSNA)
4/17
Photograph of the front of the original Stradivari Betts violin. (Photo: RSNA)
CT scan of the front of the original Stradivari Betts violin. (Image: RSNA)
5/17
CT scan of the front of the original Stradivari Betts violin. (Image: RSNA)
This image, derived from the OsiriX DICOM image viewer, is a single frame from a 3-D volume rendered movie of the 1704 Stradivari Betts violin. (Image: RSNA)
6/17
This image, derived from the OsiriX DICOM image viewer, is a single frame from a 3-D volume rendered movie of the 1704 Stradivari Betts violin. (Image: RSNA)
Photograph of the Stradivari Betts violin reproduction. (Photo: RSNA)
7/17
Photograph of the Stradivari Betts violin reproduction. (Photo: RSNA)
CT scan of the front of the original Stradivari Betts violin. (Image: RSNA)
8/17
CT scan of the front of the original Stradivari Betts violin. (Image: RSNA)
CT scan of the back of the original Stradivari Betts violin. (Image: RSNA)
9/17
CT scan of the back of the original Stradivari Betts violin. (Image: RSNA)
Photograph comparing the original Stradivari Betts violin with the carved plate of the reproduction. (Photo: RSNA)
10/17
Photograph comparing the original Stradivari Betts violin with the carved plate of the reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the front plate of the Betts violin reproduction. (Photo: RSNA)
11/17
Photograph of the CNC machine carving the front plate of the Betts violin reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
12/17
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
13/17
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
14/17
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
15/17
Photograph of the CNC machine carving the back of the Stradivari Betts violin reproduction. (Photo: RSNA)
16/17
17/17
View gallery - 17 images

Almost three centuries after Antonio Stradivari's death he remains the greatest luthier of all times, with roughly 650 out of 1000 violins of his making still testifying to his exquisite craftsmanship. As many of the surviving instruments adorn museums and private collections, playing a Stradivarius violin is a privilege reserved for few and envied by many. But this may soon change thanks to a radiologist and two violin makers who decided to harness computed tomography (CT) imaging and special manufacturing techniques to create a reproduction of a 1704 Stradivarius violin.

Dr. Steven Sirr, a radiologist at FirstLight Medical Systems in Mora, Minnesota, and professional violin makers, John Waddle and Steve Rossow, decided to recreate the instrument known as "Betts" with an unprecedented level of accuracy. Their goal was to gain a better understanding of what makes Stradivari's work superior and then use this knowledge to provide young violinists around the world with affordable replicas.

Photograph of the Stradivari Betts violin reproduction. (Photo: RSNA)
Photograph of the Stradivari Betts violin reproduction. (Photo: RSNA)

First, Betts was snatched from the U.S. Library of Congress and scanned with a 64-detector CT to create over 1000 CT images. These images, converted into stereolithographic files, were then fed into a CNC router, custom made by Rossow. The machine carved the scroll and the front and back plates of the violin from different woods. Then Rossow and Waddle finished the pieces, put them together and varnished the instrument.

"CT scanning offers a unique method of noninvasively imaging a historical object," said Dr. Sirr. "Combined with computer-aided machinery, it also offers us the opportunity to create a reproduction with a high degree of accuracy." This is achieved by measuring not only size and shape, but also wood density and the fluctuations of thickness and volume. This means the technique can be used to identify precious instruments and even establish their unique repair history on the basis of evidence such as cracks and worm holes. Such information may be extremely valuable since Stradivari's violins tend to cost a fortune.

Photograph of the CNC machine carving the front plate of the Betts violin reproduction. (Photo: RSNA)
Photograph of the CNC machine carving the front plate of the Betts violin reproduction. (Photo: RSNA)

That's a whole lot of ramifications for a project born out of curiosity. Dr. Sirr, himself an amateur violinist, first scanned an instrument in late 1980's. "I assumed the instrument was merely a wooden shell surrounding air," he said. "I was totally wrong. There was a lot of anatomy inside the violin." See this video to find out for yourselves what he found inside Betts.

View gallery - 17 images
11 comments
11 comments
Oztechi
But the vital question has not been answered...does the copied violin sound and play exactly like the Stradivarius violin it is based on?
Christian Galles
wood grain is a factor?!
Sambath Pech
I guess he is an \"amateur\" as stated in the article. I was in orchestra for almost 9 years, and the biggest factor of how a violin sounds is the type of wood that was used and how old it is (the biggest factor). A new violin will never sound the same as a 40 year old violin....even if they\'re exact replica\'s because the 40 year old violin\'s wood has been naturally drying for the past 40 years. I don\'t know the physics behind it, but I guess the structure of the wood changes as it dries and ages - changing the vibrance of the violin? It is just like whiskey, you can\'t make a 4 year old whiskey taste the same as the one that had been aging in the barrel for the past 18 years.
Scott Nathan
Anyone who has been in the same room as a Strad being played will likely acknowledge that the voice of God can not be recreated by a CNC mill. Sambath makes an excellent point about aged wood. Even modern guitar companies have decades old wood to make their guitars. In the case of the Cremonese master violin makers, there has been much speculation. The forumlae of the varnishes, the various types of molds that grew on the the maple as it traveled downstream. The strain of maple & where it grew.
The attempt to recreate the sound of a Stradivarius has gone on for hundreds of years. This sounds like an amateurish start. I\'m not saying it\'s technologically impossible, but this is NOT craftsmanship. It\'s computer science.
TogetherinParis
Like human anatomy, only from a knowledge of many individuals can we be lead to truth. Humanity should insist that all Strads are so analyzed.
Clint Ferreira
I\'m sure this debate will go on forever, but Bob Taylor, the founder of Taylor Guitars argued that the wood wasn\'t the biggest issue. He made the pallet guitar to prove his point. http://www.taylorguitars.com/guitars/archive/older/pallet.html I am not suggesting a taylor is a Stradivari, but it is a fine instrument. Later he purchased a large lot of historic trees that were used in colonial times as meeting places. He built a series of guitars more to pay homage to the historical significance rather than the tonal quality of the very old wood. http://www.taylorguitars.com/News/NewsDetail.aspx?id=32
Christopher DeMars
Stradivarius violins sound good because the wood they used was infested by a fungus due to a climate cool down during that time.
http://www.sciencedaily.com/releases/2009/09/090914111418.htm
Reproducing the exact shape of a Stradivarius is cool and all, but at least make it out of the right materials.
kendall
.The Secrets of the Stadivarious are many, so are the related Urban Legends. Some facts: the wood used in those times, from that part of Italy, virtually doesn\'t exist any more. Trees growing on the tops of hills where the soil is poor, water scarce, and wind the worst, will create a strong cellular structure that will resonate much better than those growing in the valley with ample soil, good water, little wind, having an easy life. This old growth has long since been harvested. After being cut into workable sized slabs an aging process of at least 50 years is necessary. There are many tricks to test for the tone of the wood during the construction process. Books have been written over varnish and glueing. Yes, after completion aging helps, but most important is how the violin is \"played in\". Ant. Strat. Had the luck to have his violins picked up by some of the better/best players of that time. They were given a great, and necessary, start in life by being played full, in true tones and using good techniques. Violins will have a life expectancy of about 350 years. Strats. have a quick response, building to full resonance on any tone with a great dynamic range and an evenness of volume throughout the tonal range. They are soft under the ear but project the sound relatively, quite far due to more pure wave forms and controlled harmonics. Part of the design of the violin and the bridge is to soften or eliminate unwanted tones and harmonics. A.S. designed the \"modern\" bridge which has not really been improved upon. Those little scrolls are not just for decoration, they vibrate at certain frequencies absorbing energies to help give a more even volume and pure tone.
Page Schorer
I wish they would do one of his guitars, which I understand have died of old age. Be great to hear what they sounded like when they were alive.
Zom LaCroix
@Page Schorer: there\'s a strad guitar at the national music museum in south dakota, and another in the ashmolean museum at oxford, england. don\'t think they\'re played though :(
Load More