A Stradivari Good Copy

To say that a violin made by master luthier Antonio Stradivari (1644 – Dec. 18, 1737) is priceless is an understatement. His are some of the finest stringed instruments ever made, often selling for several million dollars – that is, when they are lucky enough to be found and put on the market. Of the estimated 1,000 violins Stradivari made, there are only about 650 still in existence. The Library has three of them (and a few violas and violoncellos he also made).

Violin by Antonio Stradivari, Cremona, 1704, “Betts” / Michael Zirkle

People have been copying these and other Stradavari instruments almost ever since they were first produced. And, while owning an original may be unattainable, thanks to some cool science, getting your hands on a pretty spot-on copy could be well within reach.

Minnesota radiologist Steven Sirr, along with violin makers John Waddle and Steve Rossow, have conceived a way to replicate a Stradivarius through CT scans. Using computed tomography (CT) imaging and advanced manufacturing techniques, they recently built a reproduction of one of the Library’s Strad violins – the “Betts,” dated 1704. Their goal was to “understand how the violin works” and to make reproductions available to “young musicians who can’t afford an original.”

Metallic aura scan of “Betts” violin / Steven Sirr


More than 1,000 CT scan images of the “Betts” were produced and then converted to a program that instructs a machine to replicate those elements. Then, Waddle and Rossow finished, assembled and varnished the replica by hand. What resulted was an instrument with a sound quality very similar to an original Strad, according to Sirr, who is also an amateur violinist.

Scan of front detail of “Betts” violin / Steven Sirr

This isn’t the first time Library strings, including the “Betts,” have been scanned. Through a project with the Smithsonian Institution, Bruno Frohlich, a research anthropologist with the Museum of Natural History, has scanned nearly 50 violins and other stringed instruments – by Stradivari, his peers and today’s artisans – to study their anatomy of design and hopefully uncover that elusive sound secret.


  1. Bob Herrmann
    December 16, 2011 at 9:29 pm

    With all the talk of hightec
    No one can make a good copy
    How did Stradivari make it
    The glue and wood and strings.
    Did anyone check on the brass and steel back then.
    They must have different amount of copper, etc.etc.
    The wood was old before too.

  2. Evelyn Roberts
    December 17, 2011 at 5:47 am

    Duplicating the soul of harmonics of tree wood exactly is not possible it seems. Admirable try though.

  3. Cynthia
    December 17, 2011 at 10:54 pm

    This is very cool. Thanks! Any plans for a concert featuring the original and the copy?

    • Erin Allen
      December 21, 2011 at 12:19 pm

      Actually the Library regularly holds concerts featuring our historical string instruments. In fact, this past Saturday (Dec. 17), the Borromeo Quartet played our Strads in the Library’s annual Stradivari memorial concert. I don’t know that we have any plans to do a side-by-side concert with the “Betts” and this replica. You may find this article interesting. Nicholas Kitchen of the Borromeo Quartet actually compared the sound of five of the Library’s violins, including the “Betts.”

  4. Player
    December 18, 2011 at 5:10 am

    Thank you for this very interesting article on violin design.

    Are such replications available for sale ? If so, where and how much ?

  5. Larry Outtrim
    December 18, 2011 at 6:08 pm

    How do you get a stradivari priced or to check to see if it the real thing???

  6. Kyle Reddingfield
    December 21, 2011 at 6:24 am

    This is fascinating! Nothing sounds as beautiful as a Stradivarius, and it’s interesting to see that some people are REALLY into the science behind it all too 🙂

  7. David Arthurs
    October 8, 2012 at 10:42 am

    @Bob Herrmann:

    A violinist changes his/her strings regularly. They are useless after several months, or for some violinists less, depending on string quality and playing frequency. There are certainly no strings still played on after centuries!

  8. Mike Perera
    January 12, 2014 at 3:37 am

    You may carbon copy the structure. But you cannot duplicate the sound it produces. that is the secret .

  9. Paul Kemner
    November 27, 2014 at 11:14 am

    What most people forget is that the Strads (Amatis, etc) were all made as Baroque violins, and played that way for quite some time before being taken apart and modified.

  10. James Mckee
    February 14, 2017 at 8:31 am

    Interesting idea in a lab,but for violin makers to partake?, come on man …Human CREATIVITY !. Are you guys that desperate!. A bit disrespectful to Stradivari wouldn’t you think!. What’s next a computer that can paint like Rembrandt, or a computer that can write music? or great novels , what’s even more crazy is, violin makers them selves, trying to do this, and then people buying into it$$?.
    Living breathing artists of any craft shouldn’t be compared or contested bye any computer its sad and disgraceful. Genius creativity created bye a living breathing organism with a SOUL is something way beyond any computer. And one should of course stop to think if one should ?, Dont get me wrong I love computers, but Step back and look”and see how all of this Looks ! Cheep!.

  11. Richard Perras
    November 19, 2017 at 7:37 pm

    One makes a Violin and in the process a part of himself is implanted into his work.One hears the machine in such computerized modelling .

  12. John
    March 15, 2019 at 9:28 pm

    If these are instruments in a tax payer facility, then I would like to see th E C.A.D. files. Seeing as I am a tax payer.

  13. R Barnes
    June 30, 2020 at 3:20 pm

    Will any of the data from such scans be made public?

    • Neely Tucker
      July 1, 2020 at 11:37 am

      Hi there,

      I sent your question to Carol Ward-Bamford, one of our music specialists. Here’s her reply:

      The scans done by Bruno Frolich and the Library at the SI were first made available to the public on the SI website. More recently they have been removed during website upgrades, and will be made available on the Library’s website when staff can return to work and resume normal operating service.

      Hope that helps!

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