Terry Riley’s 1964 composition In C comes with a set of simple instructions. The musicians play a series of 53 repeated melodic cells, largely independently of the other players, while referring to a rhythmic pulse of a single note of ‘C’ played in quavers on piano or tuned percussion. And if you start lagging too far behind the others, you can miss out a cell. It’s conceptually neat and can be played on any combination of instruments. But even Riley admits that has never heard anything like this version, which sees his love of Indian classical music – which initially inspired interest. It begins with a raga introduction or alap, then a tabla takes on the pulse and the first cell finds the musicians chanting the theme and playing it on sitars, winds and strings, both in unison and on the offbeat. Riley himself suggested they open up the composition slightly to allow soloing based on the themes, and over the course of an hour it unfolds as a kind of vast musical ritual. There are some breathtaking moments, such as when the strings suddenly sweep in en masse with a new theme, and a thrilling, virtuosic all‑percussion section.