NPR:
In the world of violins, the names Stradivari and Guarneri are sacred. For three centuries, violin-makers and scientists have studied the instruments made by these Italian craftsmen. So far no one has figured out what makes their sound different. But a new study now suggests maybe they aren't so different after all.
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They gathered professional violinists in a hotel room in Indianapolis. They had six violins — two Strads, a Guarneri and three modern instruments. Everybody wore dark goggles so they couldn't see which violin was which.
Then the researchers told the musicians: These are all fine violins and at least one is a Stradivarius. Play, then judge the instruments.