Kai Christensen of Earsense.org describes the context for Beethoven’s String Quartet, Opus 18 #4: “Beethoven worked painstakingly for two years to produce his first string quartets, Op. 18, published in 1801 in the fashion of the time as a set of six. Pre-dating them are the complete string quartets of both Haydn and Mozart, Haydn having written his last two complete quartets in the same years, finishing in 1799. Just as later composers were daunted by the supreme achievements of Beethoven before them, so Beethoven was acutely aware of the rich legacy of quartet literature already preceding him.”
CarnegieHall.com, in its Short Guide to Beethoven’s string quartets, provides an overview:
“String quartet: A composition for solo string instruments, usually two violins, viola, and cello; it is widely regarded as the supreme form of chamber music. (Grove Music Online). That’s the textbook definition. Beethoven inherited the string-quartet tradition from his predecessors and shaped it into something unsurpassed in virtuosity, invention, and expressiveness. The definition could well read, ‘Beethoven’s quartets are widely regarded as the supreme form of chamber music.’ He wrote 16 string quartets, and they reveal his evolution as a composer and a man. It’s all there: earthy wit (yes, Beethoven could crack a joke), volatile temper (his fury was state of the art), and personal sorrow (he had plenty to weep about).”
One of several modulations in this movement alone, there is an emphatic shift from Eb major (complete with a plagal cadence at 2:11) to G minor at 2:19. This energetic yet precise performance is by The Dover Quartet, which The Chicago Tribune reviewed as possessing “expert musicianship, razor-sharp ensemble, deep musical feeling and a palpable commitment to communication …”