This latest Mitchell music was presented at the 50th anniversary celebrations of the AACM at the Museum Of Contemporary Art Chicago, and finds the veteran multi-reed player leading four very different trios. The project could not be a more compelling advert for the creative dynamism of both the aforesaid institutions, as the distinct character of each ensemble is writ large on the particular pieces. A lynchpin of the Art Ensemble Of Chicago, Mitchell has developed a significant body of work since the early 1970s with groups such as Sound Ensemble and Note Factory, which are capable of creating towering columns of sound. Occasionally the work is challengingly austere, and Mitchell's focus on stark, uncommon timbres is so great as to overwhelm. Having said that, there is no denying the fearless commitment to originality, none more so than the thrilling title track of the 2CD set, which is an icily beautiful urban symphony built on careful co-ordinations of alarm clocks, church peals, police sirens and what sounds like the sensual hiss of a field of computerised crickets. The morphing chimes are effectively counterpointed by a lonely brass lament, highlighting Mitchell's skill at evoking the push and pull of mechanisation against the tide of man-made lyricism, and in this case the result is worthwhile. Bold reinforcement of Mitchell's notable stature.