The Chicago musician made his mark with Minnie Riperton and Earth, Wind & Fire at Chess Records. A new collection explores his previously unreleased solo work.Earth, Wind & Fire’s “Gratitude.” Terry Callier’s “Occasional Rain.” Minnie Riperton’s “Come to My Garden.” All three albums featured ornate sounds that fused elements of classical, psychedelic music and soul. All three nudged their creators in fresh creative directions. All three bore the hallmarks of a vibraphonist who turned into one of the most underappreciated producers of his era: Charles Stepney.Stepney is best known from his in-house production and arrangements for Chess Records, the Chicago label that highlighted blues musicians and paved early inroads to rock ’n’ roll. Working mostly behind the scenes in the 1960s and ’70s, with artists including Muddy Waters, Ramsey Lewis, Deniece Williams and the Dells, he wasn’t necessarily a household name. But those who knew, knew.“It was a sensitivity and creativity behind what he did,” Williams said in an interview. “He was very special in his sound and his deliverance. It wasn’t like anybody else.”Stepney’s career, however, was short: He died in 1976 at age 45, and while his music has lived on — and spread via samples by artists including A Tribe Called Quest, Kanye West and Solange — he hasn’t been the focus of a deep dive release, until now. Last Friday, the Chicago-based label International Anthem released “Step on Step,” a compilation of demos and experimental music Stepney crafted for himself. The set features anecdotes from his three daughters — Eibur, Charlene and Chanté — alongside sporadic studio chatter, offering a rare behind-the-scenes look into Stepney’s meticulous recording process.“When people are like, ‘Did your dad write that?’ We were like, ‘Yeah, he wrote it,’” Charlene said with a laugh in a recent video call. “Because we heard it about 50 times a day.”The Stepney sisters described their father as hard-working and stern yet fair, with a restless creative mind that never stopped taking in stimuli. They remembered the jokes he’d tell, and how — even though he was busy in the studio — they could come and hang out among the instruments in the basement, as long as they were quiet. “He didn’t always labor over one song,” Charlene said. “If he got stuck, he would put it up, label it, let it breathe, and then he’d come back to it later.”These tracks that Stepney worked on alone differ from the collaborations that helped make his name. “Gimme Some Sugar,” “Daddy’s Diddies” and “Gotta Dig It to Dig It” lean heavily into electronic funk, while “Imagination,” “That’s the Way of the World” and “On Your Face” — early versions of the noted Earth, Wind & Fire songs — feature spacey synths and canned drums, far removed from the band’s immense, brassy resonance. The six-minute “Look B4U Leap” blends rhythmic percussion and bright electric keys, and “Denim Groove” — a melodic mix of jazz and samba — sounds dialed in from the not-so-distant future, the beginnings of hip-hop culture in the early 1980s.Stepney got his start studying music theory at Wilson Junior College in Chicago and began his career playing piano and vibraphone in the mid-1950s. He almost quit the business when, flat broke and frustrated that the city’s North Side clubs were white and not booking jazz and the South Side venues weren’t paying decent wages, he nearly sold his vibraphone and got a regular job. “I was broke and convinced I would never make it in this field,” he told Downbeat in 1970. “Maybe I ought to try being a shoe salesman or bookkeeper or something.”On the day Stepney was going to drop off his large instrument to a potential buyer, Phil Wright, an arranger at Chess, called and asked him to play a recording session at the label’s studio. Stepney impressed them so much, he kept getting called back to work, and eventually became the label’s lead sheet writer. In 1967, Marshall Chess, the son of the label’s founder, tasked him with an ambitious project: helping to create the psychedelic soul group Rotary Connection, taking the bones of a white rock band and adding voices like the upstart Riperton (who had first joined the label as its receptionist) and the singer and songwriter Sidney Barnes.The group was an experiment, and Stepney its gleeful chemist, mixing gospel, strings and soulful grooves with unexpected, even jarring sounds and wordless, atmospheric interludes. Riperton, with her four-and-a-half-octave range, was the clear-cut star of the outfit, and three years later, Stepney produced and arranged her lush debut album.Williams was introduced to Stepney through Rotary Connection’s ambitious sound. “I was 16 and my neighbor rushed in with this LP,” she said, “and I saw his name in the credits. There was a feeling you got from his arrangements. You not only heard it, but you felt it.” She recalled how “Charles lifted the head of the piano and started strumming the strings with a guitar pick,” while working on “If You Don’t Believe,” from her 1976 debut. “I was there with my mouth open like, ‘Who else would think to do that?’”Stepney’s schedule was demanding, and his health suffered. He learned he was diabetic, then suffered a heart attack at the home of the record executive Clarence Avant. Eibur, his eldest daughter, said he had told her, “‘I’ve done everything I’ve ever wanted to do and accomplished, but what I really want to do is my own album.’” He was finishing Earth, Wind & Fire’s “Spirit” — completing charts while he was hospitalized, Charlene said — shortly before a second, fatal heart attack.Stepney left behind 90 reels of unreleased solo material, which sat with the sisters for decades before they finally got it transcribed, with help from the International Anthem co-founder Scottie McNiece. “Stepney’s story is so uniquely Chicagoan,” he wrote in an email. “He was an incredibly gifted artist who was more focused on the music than any sort of lifestyle or celebrity. He was just a true, craft-focused, working artist.”“Step on Step” traverses the vast scope of Stepney’s creative affinities in a 78-minute set. “It’s a legacy of love; it’s a legacy of passion,” his youngest daughter, Chanté, said. “He was underrated, under-known, but he was magnificent.” More