The clarinet emerged in roughly its modern form in the early 1700s, but it took nearly a century for it to become a regular presence in chamber music and the orchestra. When Mozart visited Mannheim in 1778, the instrument was still a novelty in its “famous court, whose rays like those of the sun illuminate the whole of Germany.” Mozart was impressed, writing to his father in Leipzig: “if only we had clarinets!” back home. (Meanwhile, he complained about the flute: “my mind gets easily dulled, as you know, when I’m supposed to write a lot for an instrument I can’t stand.”)
Three years later, Mozart would get his wish—though he was by then in Vienna, rather than in Leipzig. Anton Stadler, along with his brother Johann, had become the first fulltime clarinetists in the Viennese court orchestra. Mozart and Stadler belonged to the same Masonic lodge, and they became frequent collaborators through the 1780s and early ’90s. Stadler premiered Mozart’s Kegelstatt Trio, the Clarinet Quintet, and the Clarinet Concerto, and he played in the pit for the operas Così fan tutte and La clemenza di Tito. After Mozart died in 1791, Joseph Haydn paid tribute to his young departed friend by including clarinets in final symphonies. And curiously, when his estate was settled, Stadler was found to be one of very few people who owed Mozart money, rather than the other way around.
1789 was an unusually fallow year for Mozart, who was dealing with the poor health of his wife, Constanze; the death of their infant child (the second in two years); and various financial problems. The Clarinet Quintet was one of few bright spots. The idea of mixing a woodwind instrument with strings was not new—he had written four flute quartets and an oboe quartet years earlier—but those were mostly cheerful works in the light divertimento style. The clarinet quintet follows more closely his moody viola quintets of 1787.
Another clear influence on the quintet is opera—some of Mozart’s only other significant works from 1789 were a series of “insertion arias” he wrote for a revival of Le nozze di Figaro as well as another opera by his Spanish colleague Martín y Soler (it wasn’t unusual at the time for composers to write substitute arias for other people’s operas). The clarinet traces the contours of a lyric soprano, while the other instruments add a rich internal drama.
Mozart completed the clarinet quintet and entered it into his catalogue on September 29, 1789, and it was premiered just before Christmas on a fundraising concert for widows and orphans. Stadler played it on the basset-clarinet, a special instrument of his own invention with an extended lower range. He later lost the music—or perhaps refused to hand it over to Mozart’s widow—and only a version for standard clarinet survives.
The first movement is built on a chorale-like melody that is quickly pushed forward. The second theme, accompanied by cello pizzicato, turns cold when the clarinet picks it up over sneaky syncopations. The slow movement is a clarinet aria, a longing love song sometimes duetted with violin over a bittersweet backdrop. The Menuetto is interspersed with two Trios (the first for strings only); a curious unresolved dissonance appears in the second. The finale is a set of variations on a rather coy theme that comes back full circle after a brief, reflective Adagio.