Prince Nicolas Esterhazy, in whose service Haydn spent a large part of his life, was an enthusiastic champion of an instrument that was in the process of disappearing: the baryton, a type of viola da gamba with sympathetic strings that were also able to be plucked. Haydn composed many works for his employer s use during the 1770s, among which were the 125 trios for baryton with viola and cello. The prince s instrument and its case are shown on the cover artwork, and can be found in the collection of the Hungarian National Museum in Budapest.