Mozart

Mozart, always keenly aware of music for dancing, held an appointment during the last three years of his life as a composer of dance music for the Imperial court. Among these works are three sets of German Dances, K600, 605, and 606. In none of them does he write a properly functional dominant ninth harmony (that is one with a direct or indirect resolution of ^6 to ^5 in the following tonic), but his treatment of scale degree ^6 is worth some attention. Two additional examples come from late sets of menuets, K568 & 599.

German Dances, K600n2, trio. We've seen this in earlier posts on Theodor Lachner and Josef Lanner: the clichéd 18th century cadence with ii6 as harmonization of a figure emphasizing ^6. It was the simplified harmonies of the Laendler tradition (without the ii6) that led to a distinct dominant ninth harmony, but we can see here that the melodic figure was already well established in concert music (or formal music for dance), too.

K600n3, trio, first strain. What I would call the "other" way to treat harmony below ^6 before the nineteenth century: as viiø7.

K600n3, trio, second strain. The double positioning of ^6 in parallel figures over tonic and dominant is straight out of the Laendler repertoire.

German Dances, K606n1. Attention to the same ^6-^5 figure but only over I. This is one of the closest imitations of the Laendler style in Mozart's music (there are others!).

Menuets, K568n1. Even in the menuets one can sometimes hear the ascending drive across a strain toward an expressive ^6 (circled), but note that Mozart uses IV in the bass.

Menuets, K599n12, trio. The figures in bars 3, 5, and 6 belong to the menuet repertoire and predate 1790 by several decades. The point of interest is the piccolo in bar 7: once again a gradual, persistent rise across the strain toward an expressive ^6 but this time it is firmly over V and on the beat. The sound of bar 7, then, is certainly that of the dominant ninth chord, even if we cannot really apply the label to the harmony.