Task: Question Generation
Input (English): Passage: Orenstein and Zank both comment that, although Ravel's post-war output was small, averaging only one composition a year, it included some of his finest works. In 1920 he completed La valse, in response to a commission from Diaghilev. He had worked on it intermittently for some years, planning a concert piece, "a sort of apotheosis of the Viennese waltz, mingled with, in my mind, the impression of a fantastic, fatal whirling". It was rejected by Diaghilev, who said, "It's a masterpiece, but it's not a ballet. It's the portrait of a ballet". Ravel heard Diaghilev's verdict without protest or argument, left, and had no further dealings with him. Nichols comments that Ravel had the satisfaction of seeing the ballet staged twice by other managements before Diaghilev died. A ballet danced to the orchestral version of Le tombeau de Couperin was given at the Théâtre des Champs-Elysées in November 1920, and the premiere of La valse followed in December. The following year Daphnis et Chloé and  L'heure espagnole were successfully revived at the Paris Opéra.In the post-war era there was a reaction against the large-scale music of composers such as Gustav Mahler and Richard Strauss. Stravinsky, whose Rite of Spring was written for a huge orchestra, began to work on a much smaller scale. His 1923 ballet score Les noces is composed for voices and twenty-one instruments. Ravel did not like the work (his opinion caused a cooling in Stravinsky's friendship with him) but he was in sympathy with the fashion for "dépouillement" – the "stripping away" of pre-war extravagance to reveal the essentials. Many of his works from the 1920s are noticeably sparer in texture than earlier pieces. Other influences on him in this period were jazz and atonality. Jazz was popular in Parisian cafés, and French composers such as Darius Milhaud incorporated elements of it in their work. Ravel commented that he preferred jazz to grand opera, and its influence is heard in his later music. Arnold Schönberg's abandonment of conventional tonality also had echoes in some of Ravel's music such as the Chansons madécasses (1926), which Ravel doubted he could have written without the example of Pierrot Lunaire. His other major works from the 1920s include the orchestral arrangement of Mussorgsky's piano suite Pictures at an Exhibition (1922), the opera L'enfant et les sortilèges to a libretto by Colette (1926), Tzigane (1924) and the Violin Sonata (1927).Finding city life fatiguing, Ravel moved to the countryside. In May 1921 he took up residence at Le Belvédère, a small house on the fringe of Montfort-l'Amaury, 88 kilometres (55 mi) west of Paris, in the Yvelines département. Looked after by a devoted housekeeper, Mme Revelot, he lived there for the rest of his life. At Le Belvédère Ravel composed and gardened, when not performing in Paris or abroad. His touring schedule increased considerably in the 1920s, with concerts in Britain, Sweden, Denmark, the US, Canada, Spain, Austria and Italy.
Output (English): Whose ballet score Les Noces is composed for voices and twenty-one instruments?