Mr. Cowley arrived on San Francisco dance floors in 1978 with an unauthorized remix, padded with billowing synthesizer additions, of Donna Summer’s “I Feel Love,” the Giorgio Moroder and Pete Bellotte production famous for replacing disco’s orchestral arrangements with all-electronic instrumentation. That he stormed the discothèque on the strength of a decadently elongated bootleg is a bit of poetic justice. Since mainstream disco regularly denied its origins among gay and African-American artists, the remix now seems a coup for the genre’s secret history.

Mr. Cowley, who was born in Buffalo, had moved to California seven years earlier. As his roommate Janice Sukaitis writes in the liner notes to “Candida Cosmica,” he sent postcards adorned with drawings of male genitalia back home to announce that he was gay. At City College of San Francisco, he withdrew into the newly established Electronic Music Lab, which had a set of early, compact analog synthesizers. Electronic music then required patience: conjuring blips and scree from fickle machines, often in laboratory-like settings, and recording them individually to tape before splicing together (hopefully) semi-coherent pieces.

Mr. Cowley and classmates Maurice Tani and Arthur Adcock constructed their own production and recording studio off campus and formed a sound design company, Short Circuit Productions. “Patrick would record a band and add so many synthesizer tracks that, by the end of the day, he’d remove the band,” Mr. Tani said in an interview. “When Patrick wasn’t at the studio, he was at the bathhouses. He was interested in the full spectrum of sex in San Francisco, and music was another way for him participate in those worlds.”

Jorge Socarras recalled how Mr. Cowley — reserved and slight, with sandy blond hair and a literary air — relished initiating him at the Jaguar bookstore, a Castro retailer known for its back-room sex club. Mr. Socarras also remembered that Mr. Cowley admired the elegantly composed gay pornography of filmmaker Wakefield Poole.

“Patrick was all about sexually charged atmospheres, places where rituals could happen,” said Mr. Socarras, whose unreleased collaboration with Mr. Cowley, “Catholic,” emerged in part from an archive belonging to John Hedges. Mr. Hedges assumed control of Megatone after Mr. Blecman died of AIDS-related illness in 1991. “It was about mythologizing, really dramatizing the experience.”

Mr. Cowley also worked with theater troupes White Trash Boom Boom and the Angels of Light, offshoots of the anarchic commune dwellers the Cockettes. Their thrift-store extravagance inspired him as much as the dank leather dens on Folsom Street. “Candida Cosmica” — which Mr. Cowley recorded with singer Candida Royalle, who later achieved fame as a feminist pornographer — includes the tellingly absurd musical theater ditty “The Tomato Song,” written from the perspective of a self-described “tomato cocktail.”