Serenade for 2 Clarinets, 2 Horns and 2 Bassoons in E-flat major K. 375

The Serenade in E-flat, K.375, exists in two versions: one for two clarinets, two horns, and two bassoons, and another for the same forces plus two oboes, forming an octet. From Mozart himself, we know a fair amount about the occasion that led to the first, six-instrument version of this work and about its early performances. Written for the sister-in-law of the court painter Hickl, it probably originated toward the end of September or the beginning of October in 1781 and was first performed on 15 October, the name-day of St. Theresa. The octet version probably arose in the summer of the following year. It is far more than a mechanical expansion of the sextet with the oboes merely reinforcing the clarinets colla parte. Not only did Mozart take advantage of the occasion to make changes in the articulation and the dynamics, but he also altered the work’s melodic substance and formal design. The two additional high-register instruments allowed him to achieve more subtle distinctions and gradations of timbre, thereby enabling him, for example, to vary the timbral homogeneity of the two clarinets. The opportunity arose to divide melodic phrases among the clarinets and oboes or to make them more brilliant and incisive by doubling them at the unison or octave.