Brahms had a particular love of chamber music, in all forms. He gave his first solo piano concert at the age of 15, but it was a concert tour at the age of 20 with the Hungarian violinist Reményi (Eduard Hoffman) in 1853 that was the most formative and far-reaching event of Brahms’ early career, and in 1862 Brahms used his first two Piano Quartets as his introduction to musical circles in Vienna.

On a visit to Meiningen in March 1891, Brahms heard the orchestra’s principal clarinetist, Richard Mühlfeld, play one of the Weber clarinet concertos. The composer was deeply impressed, and that summer at Bad Ischl he composed the Clarinet Trio, Op. 114, and the Clarinet Quintet, Op. 115. He played in the premiere of the Trio himself, and so enjoyed the experience that in the summer of 1894, again in Ischl, he wrote the two Sonatas of Op. 120 – his last chamber music – to play with Mühlfeld.

Brahms also loved the rich, warm sound of the viola, and created a viola alternative for the Clarinet Trio (as he had earlier for the Horn Trio, Op. 40). Within days of sending the Clarinet Sonatas to his publisher, Brahms sent in alternative parts for viola. (They were published simultaneously in June 1895.) These were certainly commercial transpositions, about which Brahms was always ambivalent, but he did undertake the task himself in these cases and produced well-considered reworkings. There are passages that are revoiced, usually transposed down an octave, to take advantage of the husky throb of the instrument’s low C-string, and there are other places where phrases are extended a few notes beyond what lies in the clarinet part or recomposed for double stops. (Brahms also arranged the Sonatas for violin and piano.)

The F-minor Sonata is the more conventionally structured of the two, in four movements, and the more demonstrative – it begins with an Allegro appassionato, for example, where the second Sonata opens with an Allegro amabile. The four-bar piano figure in octaves that launches the work is as important as it sounds. Recent analysis has demonstrated that all the subsequent ideas in the entire Sonata can be derived from this passage, connections that are sometimes obvious, other times thickly veiled. The movement generates considerable dramatic thrust, despite regularly running into soft sonic bumpers. A canonic coda brings the movement into the quiet repose of F major.

The middle movements are both in the relative major and in A-B-A form, a sort of Viennese song-and-dance team. The second movement is an elegant nocturnal aria for the viola, though the piano does get a turn with the highly embellished melody. Its partner is a dance, at first gentle, then bumptiously kinetic, “an Allegretto grazioso whose idyllic charm and serenity bring to mind the Ländler of Schubert and of Brahms himself,” according to the critic and devout Brahmsian Eduard Hanslick.

The Sonata’s progression from dark to light is completed in the finale, a sonata-rondo romp of almost Haydnesque impertinence, but thoroughly Brahmsian structural rigor. The three chiming notes at the beginning return to cue the major points, however, and the prevailing chuckling provides a blithe cover for the complexities and carries the piece to its exuberant conclusion.

John Henken is Director of Publications for the Los Angeles Philharmonic.