Final answer:
The focus on timbre in Webern's music is associated with Serialism, a technique that emerged in the early 20th century and is characterized by a departure from traditional tonality, often employing a twelve-tone technique.
Step-by-step explanation:
The focus on melodies made up of timbre, or sound-color melody, is associated with the music of Anton Webern and represents a key aspect of Serialism. Serialism, a technique developed in the early 20th century, is closely tied to the music of the Second Viennese School, which included composers like Arnold Schoenberg. Unlike traditional Western music that relied on tonality or a central key, Serialism and its related form, atonality, do not adhere to such musical norms. Schoenberg's innovative approach often involved a twelve-tone technique that ensured all notes of the chromatic scale were treated with equal importance, dissolving traditional harmonic expectations and creating a sense of musical equality without a central key. This technique contrasted sharply with the tonality used in Renaissance and Romantic music, which was based on a hierarchical system of scales and key centers.