On 5 October 1948, RDF broadcast Schaeffer's Etude aux chemins de fer. This was the first "movement" of Cinq tudes de bruits, and marked the beginning of studio realizations[38] and musique concrte (or acousmatic art). Schaeffer employed a disc cutting lathe, four turntables, a four-channel mixer, filters, an echo chamber, and a mobile recording unit. Not long after this, Pierre Henry began collaborating with Schaeffer, a partnership that would have profound and lasting effects on the direction of electronic music. Another associate of Schaeffer, Edgard Varse, began work on Dserts, a work for chamber orchestra and tape. The tape parts were created at Pierre Schaeffer's studio and were later revised at Columbia University.