Pyramid Song” is a piano-driven piece with vocals and lyrics by Yorke. It also features string orchestrations by band member Jonny Greenwood. The song builds to a climax with the introduction of Phil Selway’s jazz-influenced compound rhythm and the siren-like wails of the Ondes Martenot, an early electronic instrument also played by Jonny. Colin Greenwood plays upright bass rather than his usual electric; O’Brien adds subtle electric guitar to live versions, playing with lots of delay. Read more on Last.fm.