To composers in the first decades of the 20th cent., the ever more complex harmonies of late romanticism, especially in the works of Liszt and Wagner, seemed to be leading inevitably towards music in which there was no identifiable sense of key at all. Schoenberg took that final step into the unknown in the finale of his Second String Quartet in 1908. Over the next decade, he and his pupils Berg and Webern produced a series of masterpieces that celebrated the freedom of atonality, before they began to look for a new way of systematizing their language — Andrew Clements