The American jazz pianist, clarinettist and composer Muhal Richard Abrams, who has died aged 87, was one of contemporary music’s most dedicated and free-thinking sages – a fascinated and fascinating investigator of modern musical sources, from the early-jazz piano styles of stride and boogie-woogie through to compositional methods embracing Duke Ellington and Schoenbergian serialism, free-jazz and the blues.

Largely self-taught, Abrams studied jazz’s piano greats in his youth until he could hold his own in the Chicago South Side’s jazz clubs. He went on to compose symphonic works, pieces for all-saxophone ensembles, collages of speech and abstract sound and music for string quartet. As a solo pianist he avoided conspicuous virtuosity in favour of patient exploration – an unhurried personal synthesis of rootsiness, lyricism and abstraction, interweaving blues motifs, fragmented bebop figures, classical music and free-improv.

He won many awards in his long career and recorded extensively with many of jazz’s most illustrious innovators. But perhaps his most lasting legacy was as co-founder, in 1965, of the Association for the Advancement of Creative Musicians (AACM), a Chicago-based collective that continues to support the recording and live performance of new, original music. Abrams saw the early AACM partly as a promotional organisation, but mainly as a workshop to which players and composers could bring works in progress – to have them edited, tested and reshaped by sympathetic improvisers. In this it was reminiscent of the impromptu rehearsal and workshop methods common to various bands, from Ellington’s in the 1930s and 40s to the UK’s Loose Tubes in the 80s.

Muhal Richard Abrams’ Experimental Band

Born Richard Abrams in Chicago as the second of nine children to Milton, a handyman, and his wife, Edna, he attended the city’s largely African-American DuSable high school, which was much respected for its music teaching under Walter Dyett. But at the time Abrams preferred sport, not music, and he left at 15.

Going on to study with a local church pianist, he picked up jazz-composing tips from his neighbour, Will Jackson, a trumpeter in the popular Jimmie Lunceford band, and mostly developed his fluency in mainstream jazz and bebop piano styles through his own efforts. He also grew fascinated by the ideas of the Russian expat composer, theoretician and early electronics experimenter Joseph Schillinger, whose mathematical musical theories had also intrigued popular composers and bandleaders such as George Gershwin and Benny Goodman.

Abrams began recording in 1957 with the drummer Walter Perkins’s bluesy hard-bop band, MJT + 3. He wrote arrangements for the Chicago bandleader Walter “King” Fleming, accompanied visiting jazz celebrities to the midwest such as Miles Davis, Dexter Gordon and Sonny Rollins, and worked in the saxophonist Eddie Harris’s popular blues-bop group.

Gradually he sought inspiration in more freely improvised music and began to mine non-jazz sources, including the use of found objects and contemporary classical ideas, as well as electronics. In 1961 he created a workshop project, the Experimental Band, and four years later, with regular jazz employment prospects retreating before the advance of progressive rock and funk, the venture expanded into the AACM, dedicated in its charter to the nurturing of “serious, original music”.

The organisation drew in many of Chicago’s leading young jazz radicals, including the trumpeter Lester Bowie and the saxophonists Roscoe Mitchell and Joseph Jarman. Other AACM luminaries included the multi-reeds player and composer Anthony Braxton, the trumpeter Wadada Leo Smith, the violinist Leroy Jenkins, the Miles Davis drummer Jack DeJohnette and the singer/pianist Amina Claudine Myers.

Interview with Muhal Richard Abrams

Abrams adopted the forename Muhal in 1967, a word of obscure origin that he maintained meant “No 1”. In the late 60s and early 70s he began to record extensively with AACM members for the Chicago indie label Delmark, playing the clarinet as well as the piano alongside Braxton, Jenkins and others on his sombrely lyrical album Levels and Degrees of Light (1968). He touched on the landmarks of jazz-piano history, with a quintet including Smith, on Young at Heart Wise in Time (1969) and reworked ragtime, boogie and other popular forms within a loose free-jazz setting on Things to Come from Things Now Gone (1975).

In the early 70s AACM’s cohesion had begun to fragment as some members (notably the Art Ensemble) sought more sympathetic audiences in Europe, and in 1976 Abrams moved to New York, subsequently opening a local chapter of the AACM there. AACM musicians including Abrams and Braxton often performed on the converted-warehouse “loft scene” of that decade, and from the late 70s to the 90s he regularly recorded with lineups of varying sizes for the Italian label Black Saint, paying ruggedly oblique tributes to African-American giants, from Ellington to Muddy Waters, and occasionally playing the synthesiser.

At the turn of the century he began exploring more intimately cutting-edge and chamber-musical settings with the violinist Mark Feldman, and computer-aided ventures with his old AACM associates George Lewis (trombone, laptop) and Mitchell (sax). Abrams also fulfilled contemporary-classical commissions from the Kronos Quartet and several symphony orchestras, and served on various arts funding panels, always seeking to open up new categories for grants and fresh attitudes to creativity.

Abrams was the first recipient of Europe’s biggest jazz award, the Jazzpar prize, in 1990. But the most prestigious of the many official accolades that came his way was a National Endowment for the Arts jazz masters’ fellowship, the US’s highest honour for jazz musicians, which he received in 2010, when he performed both a long piano improvisation and conducted the Jazz at Lincoln Center orchestra at the New York ceremony.

Muhal Richard Abrams performing in Chicago in 2015. Photograph: Robert Abbott Sengstacke/Getty Images

He continued to perform in his 80s, and a memorable appearance came at the 2013 Chicago jazz festival with Mitchell, Henry Threadgill (reeds), DeJohnette (drums) and Larry Gray (bass). The concert was recorded by the ECM label and released under the title Made in Chicago in 2015. In that anniversary year for AACM, Abrams performed extensively, notably at the Newport jazz festival with the Made in Chicago group.

“He was able to create a community of artists who all respected each other, all shared the responsibility of playing with each other and all actually taught each other,” said Smith. Those words catch just how attuned Abrams was to the way jazz works.

He is survived by his wife, Peggy, daughter, Richarda, six siblings, three grandchildren and five great-grandchildren.

• Muhal Richard Lewis Abrams, musician, born 19 September 1930; died 29 October 2017