Basset Horn - Image 1

Invented about 1770, the basset horn is a clarinet whose range is extended down a major third below the lowest note of the regular clarinet. This is made feasible to play by angling the top half of the body back and providing a box (kasten) in which the tubing makes three turns before reaching the metal bell. Mozart (1756-1791), whose great operas, like Don Giovanni, were very popular in Prague, was fond of writing for the basset horn, particularly in his Masonic pieces, as well as the Requiem, left uncompleted at his death in 1791. The NMM's instrument was built two years later. Mozart and Doleisch certainly would have known each other.