From Science Daily

Spanish Stradivarius II of c. 1687, on exhibit at Palacio Real de Madrid. (Credit: By Håkan Svensson (Xauxa)
A good violin depends not only on the expertise of the violin maker, but also on the quality of the wood that is used. The Swiss wood researcher Professor Francis W. M. R. Schwarze (Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland) has succeeded in modifying the wood for a violin through treatment with special fungi. This treatment alters the acoustic properties of the instrument, making it sound indistinguishably similar to a Stradivarius.