One might worry that a scherzo and a capriccio would be too similar in nature to be placed comfortably next to one another in a multi-piece work like Mendelssohn's Opus 81 (posthumously published in 1850); but the Capriccio in E minor for string quartet, Op. 81, No. 3, is so different from the preceding scherzo that there is never a hint of trouble. The capriccio has two separate sections of music, utterly contrasted to one another, and not at all of equal duration. First is lugubriously melodic Andante con moto, its melody sung out by the first violin with rich, gooey bass support of the cello and the offbeat filler from the viola and second violin. But 28 bars later we realize, if we perhaps hadn't yet, that this has all been just a preparation for the real meat of the capriccio, which, after a tiny quasi-cadenza for the first violin, arrives in the shape of an Allegro fugato, assai vivace. True to its name, this music is quite fugal, using a subject built from two outbursts of sixteenth notes and a slowly rising follow-up idea.

Listen to the wonderful way that Mendelssohn uses the head gesture of the subject as a counterpoint to the next subject statements, simply throwing it over by half a bar so that within the fugal exposition itself there is already something very like stretto! Mendelssohn indeed finds this fertile ground—again and again he finds new ways of playing out the "burst" idea against itself, extending it, varying it, turning it upside down. Finally, a fortissimo climax pits the idea in all four voices against one another and, as a last passionate gasp, the once restrained follow-up idea is played as a series of slam-bang sforzandi. Three chords, as traditional a cadence as one might write, bring an end to this most overtly passionate fugue.

© Blair Johnston, All Music Guide