Robert Wyatt may have retired from music, but what a wonderful legacy he's left: almost 50 years of avant-pop genius, taking in collaborations with everyone from Björk and Brian Eno to Ivor Cutler. Compiled by Wyatt and his biographer Marcus O'Dair, Different Every Time is a thoughtful two-disc overview of the great man's career, encompassing solo tracks and collaborations from 1970 to 2009. Throughout it all, there's that beautiful Wyatt voice, like an English ex-choirboy intoxicated by the moonlit jazz inflections of Chet Baker.

In avoiding too much overlap with 2004's Greatest Misses, this set leaves out the sublime 'Sea Song' from 1974's essential Rock Bottom. Instead, we get an incredible live version of that album's 'Last Straw', with Wyatt scatting ecstatically over his band's oceanic jazz-rock. It's a joy to hear two songs by Matching Mole, the group Wyatt formed after leaving Soft Machine in 1970, not least 'Signed Curtain', a charmingly self-conscious piano ballad which delivers a real emotional payoff by the end.

The author Jonathan Coe has described Wyatt's words and music as a continuous, alternative running commentary on the past few decades; 'sane songs for insane times'. Wyatt's left-wing politics are most evident in 1980s recordings like 'The Age of Self' and the Chilean liberation anthem 'Vencemeros (We Will Win)', recorded with Working Week and Tracey Thorn, but a deep sense of humanity pervades all his music, while his surrealism and humour ensure his songs never descend into dreary agitprop.

The second disc uncovers rare gems like the mournful post-punk chamber pop of Epic Soundtracks 'Jelly Babies' and Wyatt's starkly beautiful acapella reading of John Cage. Other highlights include the Cuban glam glide of Roxy Music guitarist Phil Manzanera's terrific 'Frontera' and the luminous jazz-pop of Jeanette Lindstrom's 'The River'. Oblique English magic.