Le quatuor à cordes reste une épreuve, au sens initiatique du terme » (The string quartet remains a test, in the initiatory sense of the term)
said Boulez in 1985. Composed in 1948, revised in 1960 and simplified in 2012 it is an extremely difficult work for a string quartet. Boulez distinguishes in his music two types of durations: one smooth, the other striated. The Livre pour quatuor is worse than striated: scratched, hatched, zebraed by the tears of the pizzicati, while the strings of the instruments are struck with the wood of the bow, the key or the easel. Splendid mastership of sound and use of the stringed instrument – he worked on it until he was almost 90 years old!