String Quartet No. 12 (Beethoven)

The String Quartet No. 12 in E♭ major, op. 127, by Ludwig van Beethoven, was completed in 1825. It is the first of Beethoven's late quartets. There are four movements:

The first movement is twice interrupted – just before the development of the sonata form begins, and when that section is almost but not quite over – by recurrences of the opening's Maestoso music.

The immense second movement is in the subdominant key of A♭ major. It consists of a set of six variations and a coda. The first variation is in 12
8 meter with darker harmonies and quick changes in dynamics. The second variation increases the tempo to andante con moto and adjusts the meter to 4
4. Here, the two violins engage in a dialogue over staccato accompaniment. The third variation shifts to E major, enharmonically the flat submediant, and the tempo shifts to a hymn-like adagio molto espressivo. The fourth variation returns to 12
8 and the key of A♭ by dropping a half-step from E to the dominant note (E♭). This variation has a codetta which transitions the key to D♭ major in preparation for the next variation. The fifth variation is sotto voce and has been called a "mysterious episode" and begins in D♭ major and transitions to the parallel C♯ minor. The recapitulatory sixth variation returns to 12
8, presents only half of the theme and connects directly to the coda.

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