See the band preparing to play '15 Step'
To watch the footage, which was shot by USC members, scroll down and click on the video below.
The nine-minute video shows frontman Thom Yorke giving the marching band – which included drummers, tuba players and trumpet players – instructions as they rehearse ’15 Step’ at Sony Studios in Los Angeles.
A relaxed-looking Yorke comments that the “snare drums are too busy” in the video, before launching into the song.
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