The Clarinet Concerto in A major K622 by Mozart, was completed in October 1791 for the clarinettist Anton Stadler. It consists of three movements, in a fast–slow–fast succession. 1. Allegro, 2. Adagio, 3. Rondo. The work was completed a few weeks before the composer’s death, and has been described as his swan-song and his last great completed work. The date of its first performance is not certain, but it may have been 16 October 1791 in Prague. There is no surviving autograph for the concerto, and the printed score was published posthumously. The only relic of the work written in Mozart’s hand is an excerpt of an earlier rendition written for basset horn in G. This excerpt, dating from late 1789, is nearly identical to the corresponding section in the published version for A clarinet, although only the melody lines are completely filled out. After rethinking the work as a basset clarinet concerto, Mozart gave the completed manuscript to Stadler in October 1791.
Several notes throughout the piece go beyond the conventional range of the A clarinet, but the basset clarinet was a rare, custom-made instrument, and when the piece was published after Mozart’s death, a new version was made by unknown arrangers, with the low notes transposed to regular range. Objections were raised to this: a reviewer in the Allgemeine musikalische Zeitung commented that although the transpositions made the work playable on normal clarinets, it would have been better to publish Mozart’s original version, with the alterations printed in smaller notes as optional alternatives.
The clarinettist Alan Hacker commented in 1969 that if the original manuscript had been published, “manufacturers would have made and sold basset clarinets by the thousand”, but the manuscript was lost. Mozart’s widow told a publisher that Stadler had either lost it, pawned it or had it stolen from him. In 1801 three different publishing houses – André, Sieber, and Breitkopf & Hartel – published editions of the work, all with the solo part adapted for the standard clarinet. These became the standard performing editions.
The basset clarinet fell out of use after Stadler’s death and no original instruments from his time have survived. The instrument was revived in the latter part of the 20th century: attempts were made to replicate the original version, and new basset clarinets have been built for the specific purpose of performing Mozart’s concerto and clarinet quintet. Some have been based on 1790s engravings showing Stadler’s instrument. The first performance of a reconstructed version of the original was in 1951; Jiří Kratochvíl’s reconstruction was played by the clarinettist Josef Janouš.
