Artist Christian Marclay gives shape, form and colour to sound

He creates endless loops, reconstituted vinyl records and some of the boldest, most creative film montage in the contemporary art world. Christian Marclay has been exploring sound, visuals, collage and reproduction for more than four decades, with multimedia installations, photographs, sound pieces and videos. He joins us as the Pompidou Centre in Paris holds a retrospective of his work. The artist tells us about seizing the ephemeral nature of music, about the existential ideas behind his 24-hour film "The Clock" and how Snapchat has provided him with a contemporary medium to extend his practice.