The world auction record for a musical instrument has been broken, but only Sotheby’s and the buyer know exactly by how much. The price for the violin, a Guarneri, was “well in excess” of the $3.54 million paid for a Stradivarius in 2006. New owner Maxim Viktorov loans his instrument collection out regularly and this new acquisition will be played by Pinchas Zukerman next month in Moscow.