The fantastically named Non-Cognitive Aspects of the city is the first Art Ensemble of Chicago release since 2004’s Sirius Calling; the first exclusively live recordings made widely available since 1984’s Live in Japan; the first time the band has configured as a quintet since the early 1990s; the first release to include a trumpet since the death of Lester Bowie in 1999; and the first since the passing of founder member, bassist Malachi Favors in January 2004, just two months before these recordings were made.

This double CD contains two complete sets, recorded at New York’s Iridium club during a rare six-night engagement during March and April 2004 by a rejuvenated band comprising long-term mainstays—Don Moye on drums, Roscoe Mitchell on reeds and percussion and Joseph Jarman on reeds, percussion and vocals—as well as new blood in the form of bassist Jaribu Shahid and young trumpeter Corey Wilkes, both making their recorded debut with the ensemble.

Perhaps you’d be forgiven, then, for expecting these sets to be an attempt at rediscovering an identity, regrouping and re-examining the ensemble’s approach. You’d be wrong. Instead, we have a proud, brazen embodiment of the ensemble’s long-held philosophy that the music lives independently of the band—that the ensemble will continue to perform come what may, no matter who is on the stage.

In short, this sounds exactly as you’d want and expect an Art Ensemble of Chicago disc to sound: a joyous, dizzying, restless investigation of the myriad forms of “Great Black Music” to which they’ve dedicated themselves over the last four decades, with a generous dose of dense, cerebral free-jazz holding it all together. True, the new band-members bring their own identities to the mix—and Corey Wilkes is especially impressive in the way he’s able to match Lester Bowie’s legendary, scatological horn, without ever sounding overshadowed or unduly influenced—but make no mistake: this is vintage Art Ensemble material.

Disc one kicks off with nearly 24 minutes of continuous music, presenting a series of ever-unfolding, seamlessly connected improvisations. It starts with Mitchell’s warped take on the hard-bop swinger, “Song for My Sister”, with a sly, sliding, meandering tenor solo that manages to be both comfortably swinging and tensely spontaneous, setting up a palpable anticipation of the territories yet to be uncovered. There’s a growlin’ and howlin’ trumpet solo from Wilkes, a storming drum breakdown that tips the collective effort into free energy music, a left-field, twitchy alto solo and a commanding upright bass solo backed by a fluttering, angry hi-hat and the ensemble’s trademark ‘small instruments’: a tinkling, tinkering conglomeration of xylophones, bells, duck-calls, whistles and sundry percussion. Amazingly—and this is the key to understanding Art Ensemble of Chicago—throughout all this exploration, the groove is never far away. These cats can lose themselves and still swing with both feet firmly planted in the great blues-based idiom of African-American music.

After more energy-pulse jazz and furious blowing on “Song for Charles” and impressionistic musical pointillism on “On the Mountain”, the set draws to a close with a heavy funk groove on “Big Red Peaches” followed by “Odwalla”, the ensemble’s traditional, swinging farewell theme-tune, regularly used to end a gig for more years than their current trumpeter has graced this earth.

Almost unbelievably, in terms of sustained invention, the second set manages to outdo the first, starting with a full 40 minutes of spontaneous, uninterrupted creation. “Erika” starts off as a loose, mellow, water-colour blues making the old Beat jazz-and-poetry connection with Mitchell’s laconic and sweetly spoken elegy to the post-‘60s experiences of black America: “Erika, child of our uncharted microtones.” As, with barely disguised emotion, Mitchell intones “Rise Up!” the horns do just that, bursting into a maelstrom of high-energy jazz, and Don Moye showing how his position as a righteous keeper of the free-jazz drummers’ flame has not been diminished by the years. From there, the set slides straight into “Malachi”, a bass-heavy, mid-tempo blues written in memory of the departed Malachi Favors, and then onto “The J Song”, which uses oriental-style xylophone and percussion with wooden flute to build an irrepressible fourth-world groove that draws to a beautiful conclusion. It’s 40 minutes of some of the tightest, most moving improvisation you’re ever likely to hear.

The set makes a more mournful turn to challenging improvisation on “Red Sand and Water”, working up to a sombre fanfare on the brief “Slow Tenor and Bass”. Inevitably, though, the set comes back to joy, finishing with “Odwala”, and, finally, Moye’s congas accompanying Mitchell’s farewell vocals:

This music comes to you with love,
This sound is the sound of life.
This music comes from us to you,
This sound is the sound of joy.

It’s a loving valediction and a blessing from wise warriors, a gift for which we should all be grateful.