Already in his early youth, Mozart made his first forays into the genre of the string quartet, the supreme discipline in chamber music. The three three-movement works K. 136–138, which he designated “Divertimento”, are dated “Salisburgo 1772” in the autograph, but were presumably conceived earlier while on a concert tour under the Italian sun. They do not yet display the “erudite” four-part writing that Joseph Haydn was perfecting at the same time, but instead strike a cheerful, playful serenade...