Any London-based fan of what Lol Coxhill called ‘squeaky bonky music’ will be familiar with Mopomoso (MOdernism POstMOdernism SO what?), the longest-running improv concert series in the UK. Only with the help of the Arts Council and Sound and Music, however, were they able spread the word beyond the capital. In 2013, nine Mopomoso regulars embarked on a rare, week-long tour to celebrate the group's 21st birthday. The watchword throughout, as tour manager Alice Eldridge states in the liner notes, was ‘mutualism’. Although many of these musicians had worked together for years, they had not previously had the chance to play together night after night. This ‘rich, cumulative’ experience is brilliantly represented in this superb four-disc set. Chasing the Peripanjandra by Evan Parker, John Edwards and Mopomoso co-founder John Russell is the obvious centrepiece, perhaps, but the other discs are as strong, including a brilliant solo set from the versatile, virtuosic Thomas and a voice-as-instrument performance by Grant that calls to mind Julie Tippets. Magnificent.