Beethoven's musical style
The compositions that Beethoven wrote in his formative period can be generally characterized by the composer's efforts to master the predominant classical language of the period. His works from this period can be subdivided into two, based on the composer's residence. First, various juvenalia, written when the adolescent Beethoven was in residence in Bonn and heavily indebted to the works of contemporaries, especially Mozart and his teacher, Christian Gottlob Neefe. These early efforts can be seen in a set of three piano sonatas and piano quartets (WoO 36) that Beethoven wrote before 1792. The Quartets, for instance, are each specifically modelled after three Violin sonatas Mozart published in 1781 – K 296, 379 and 380 – and Beethoven would later draw upon this familiarity in the composition of several of his own Violin Sonatas.
Piano Sextet (Mendelssohn)
Felix Mendelssohn's Sextet in D major, Op. 110, MWV Q 16, for piano, violin, two violas, cello, and double bass was composed in April-May 1824, when Mendelssohn was only 15, the same time he was working on a comic opera "Die Hochzeit des Camacho". Its composition took place between the Viola Sonata and the Piano Quartet No. 3. It also preceded the famous Octet, Op. 20 by about a year. 1824 is also the probable year of the composition of the Clarinet Sonata. Like the latter, the Sextet was not published during the composer's lifetime. Its first edition was issued in 1868 as a part of a complete collection of Mendelssohn's works. Hence the misleading high opus number.