Music for wind ensemble played an important role in Mozart's Austria. Known as Harmoniemusik, such ensembles were based on a nucleus of a pair of bassoons to provide the bass, and two horns. Upper parts were provided by one or more pairs of treble winds, most frequently oboes and clarinets. Dispositions of this kind not only formed the basis of military bands, but also the Hausmusik of the lesser nobility, for whom wind ensembles were not only cheaper than employing a full orchestra, but also had the advantage of being suitable for both outdoor and indoor performance. Mozart himself introduces one function of Harmoniemusik in the supper scene of Don Giovanni, where the Don is seen enjoying his supper to the accompaniment of some of the popular operatic tunes of the day played by his own wind ensemble.
During his earlier years in Salzburg, Mozart composed eight wind divertimentos, works almost certainly designed for outdoor use, and primarily intended to fall pleasingly on the ear as little more than background music. Mozart being Mozart, many movements, of course, transcend such modest pretensions. Nevertheless, the three great wind serenades Mozart composed after settling in Vienna in 1781 elevate the form to unprecedented heights. While only one, the Serenade in C Minor, K. 388, can be dated with any degree of certainty, it appears that all three were composed during the composer's first two years in Vienna. The first and most obvious difference between the Serenade in B flat and its Salzburg predecessors is the huge expansion in scale, both in terms of instrumentation and length. Instead of six (or eight) instruments, K. 361 is scored for no less than thirteen--pairs of oboes, clarinets, basset horns (lower pitched members of the clarinet family), horns in F and B flat, and bassoons, with the bottom line strengthened by a string double bass. The presence of a double bass suggests that the work was intended for indoor rather than outdoor performance; this notion is augmented by the first recorded performance, which took place at a benefit concert given on March 23, 1784 at the Burgtheater in Vienna. The concert was to benefit Mozart's friend Anton Stadler, a brilliant clarinetist and basset horn player for whom he later composed both the Clarinet Quintet in A major, K. 581 and Concerto in A major, K. 622. A member of the audience who heard the performance recorded the effect it made on him: "...glorious and sublime! It consisted of thirteen instruments...At each instrument sat a master--oh, what an effect it made--glorious and grand, excellent and sublime." One curious aspect of the report by this enthusiastic auditor is that he mentions the work as being in four movements, whereas K. 361 has no less than seven: Largo - Molto allegro; Menuetto; Adagio; Menuetto (Allegretto); Romance; Theme and Variations; Finale (Molto allegro). This leads to the conclusion that Stadler's "first" performance only included part of the work, a procedure frequently followed in early published editions. Whatever the somewhat mysterious background to this unique work, modern listeners will surely echo those sentiments penned over 200 years ago -- glorious, grand, excellent, and sublime are indeed just epithets.