It's 60 years since John Cage wrote his pivotal Music of Changes, and it's beginning to show its age. It feels very much of its time, with its uncompromising adherence to the 64 hexagrams of I-Ching, the Chinese book of changes, determining the direction of the piece and its use of sudden, percussive attacks on the strings or the body of the instrument. But for all that there is no denying the extreme stamina and concentration required of the performer, and here Tania Chen excels, bringing these strange, austere and glacially beautiful "sounding events" to startling life. No one would pretend this is easy listening but it's a small monument in the landscape of contemporary music and 20th-century western art and impossible to ignore.