Photo Gallery: When is a fiddle a violin? One day late last year, 17 experienced violinists gathered in a hotel room in Indianapolis to tackle the question. Each one in turn was blindfolded and played a few bars of Tchaikovsky’s violin concerto on six violins - two made by Antonio Stradivari, one by Bartolomeo Guarneri del Gesu and three by modern violin makers. The challenge was to distinguish the three old master violins. According to the results of the experiment published in the January