Wood density, key to Stradivarius

A Dutch doctor and a violin maker from Arkansas have compared five classical and eight modern violins in a computed tomography (CT) scanner. Apparently the 300-year-old violins are made of wood with a more consistent density than the modern violins. They aren't saying for sure that this is what gives the Stradivarius violins their unique sound, but it's the first scientific explanation that seems to have merit.

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