Moshé Mizrahi’s 1970 film Les Stances a Sophie was a witty, often amusing post-New Wave study of French gender politics. It was also criminally underseen, and might’ve been almost entirely forgotten after a three-week art house run if it hadn’t happened to have been blessed with one of the most memorable avant-jazz soundtracks to ever eclipse its source material. After Art Ensemble of Chicago took their playful-yet-perceptive take on advanced internationalist free jazz to Paris in 1969 and embarked upon their most creatively fulfilling and productive period, their colorfully eclectic and tonally unpredictable sound found one of their biggest breakthroughs through this soundtrack. The Fontella Bass-fronted J.B.’s-meet-the-Arkestra “Theme de Yo Yo” became their most recognizable song through an almost uncanny ability to balance avant-garde jazz’s tonal rule-flouting with to-the-gut funk in ways that never entirely give full reign to either mode — and feel all the more powerful for it, thanks in part to Bass’s total commitment to the surrealism its lyrics evoke with a sort of dream-logic vividness (“Your eyes are two blind eagles/That kill what they can’t see”). The other extended piece on the soundtrack, the rollicking “Thème Libre,” is the Ensemble at their most vibrant, careening through Don Moye’s tumultuous drumming with a breathtaking Lester Bowie/Joseph Jarman/Roscoe Mitchell freeform horn-section interplay — bracing stuff, but it breaks down defenses with a sense of exciting chaos you can get your arms around, played with unremitting power and joy. (It’s no less bracing in a shorter dose via “Theme de Céline.”) Meanwhile, a casually irreverent yet still heartfelt pair of brief, bop-warped pieces adapted from Monteverdi’s opera L’Arianna and the two-part late-Coltrane variations of “Proverbes” prove that free jazz can be at its most revelatory when it comes in brief, impressionistic flurries that continue inside your head long after they conclude on record.