 With both these huge projects Varèse felt ultimately frustrated by the lack of electronic instruments to realize his aural visions.Nevertheless, he used some of the material from "Espace" in his short "Étude pour espace", virtually the only work that had appeared from his pen for over ten years when it was premiered in 1947.According to Chou Wen-chung, Varèse made various contradictory revisions to "Étude pour espace" which made it impossible to perform again, but the 2009 Holland Festival, which offered a 'complete works' of Varèse over the weekend of 12–14 June 2009, persuaded Chou to make a new performing version (using similar brass and woodwind forces to "Déserts" and making use of spatialized sound projection).