What a clanger! In an act of non-intentioned randomness that might actually have pleased Cage tremendously, the cover art flags up Fourteen, Four6 and Four3 when, in fact, the first piece is Thirteen. But there’s no real harm done – the Barton Workshop might be sloppy proof-readers but these expert, devoted performances of John Cage’s late-period number pieces is compensation aplenty.

Cage’s number pieces really do contain some of the most beautiful sounds this side of silence, assuming your definition of “beauty” embraces more than perfumed decoration. Written right up until 1992, the year of his death, the works espouse Cage’s concept of “anarchic harmony” which essentially means chords, but without any of the goal-orientated principles of Western harmony that he often dismissed as pushy and manipulative. To achieve this, material is arranged into “time brackets” which indicate how long each sound should last for. Because the instrumental parts are uncoordinated, random overlaps create a profound unity between individual instrumental timbre, overall ensemble texture and the flow of static, ethereal harmonies.

The sound world of Thirteen is defined by its conventional chamber orchestra instrumentation (albeit with a subtle stress placed on lower-register instruments such as bassoon, trombone and tuba) while the two Four pieces are more open-ended – Four6 allows for “any way of producing sounds”. And it’s testament to the potency of Cage’s concept that it doesn’t much matter. This music generates itself in the moment by musicians playing as beautifully as they can within the strict constraints Cage prescribes. Instrumental allegiance is but a passing detail.