Sergei Koussevitzky was one of the world’s premier conductors and virtuoso bass players whose favorite instrument was an unusually-shaped bass reportedly made in 1611 by the Amati brothers, Antonio and Girolamo. In 1962, 11 years after Koussevitzky’s death, his widow gave the bass to Gary Karr, currently considered to be the world’s premier double bassist. In 2004, Karr donated the bass to the International Society of Bassists. Close inspection by a team of experts in 2004, however, revealed stylistic inconsistencies that suggested a later construction date. We used four reference tree-ring chronologies developed from treeline species in the European Alpine region to anchor the dates for the tree rings from the double bass absolutely in time. The bass yielded a 317-year long sequence, the longest sequence yet developed from a single musical instrument. Statistical and graphical comparisons revealed that the bass has tree rings that date from 1445 to 1761. Based on the strength of these correlations, the spruce tree harvested to eventually construct the double bass likely came from the treeline Alpine area of western Austria, not too far from Obergurgl at the Italian border. Our results demonstrate that the double bass was not made by the Amati Brothers, but likely by French luthiers in the late 18th Century.