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.