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Stratos, the Greek tenor and composer, famously collaborated with John Cage, a renowned avant-garde composer, on several projects that pushed the boundaries of traditional music. Notably, they worked on Cage's 1960 composition, Aria, which incorporated Stratos's unique extended vocal techniques, such as multiphonics, glissandos, and harmonics, seamlessly merging their artistic visions and redefining the possibilities of vocal expression in contemporary music.