Despite all the full-tilt-boogie myths about her life, it’s not true that Janis Joplin-whose larynx-shredding singing style (as on 1968’s “Piece of My Heart”) made the blues turn blood- red-never found a drug she didn’t like. “She wouldn’t smoke grass, and she didn’t like acid,” recalls her Big Brother & the Holding Company band mate, guitarist Sam Andrew, “or anything that takes your mind off business and makes deadlines hard to meet.” In fact, after temporarily kicking heroin in February 1970, she considered making ads urging people not to try the stuff.

On Oct. 4, 1970, her life became just such an advertisement when she died of a booze-and-junk OD in L.A.’s Landmark Motor Hotel. After only four years in rock’s pantheon, Joplin was dead at age 27. “People tried to tell her to slow down,” observed Bobby Neuwirth, Joplin’s friend and tour manager. “But that was like telling a B-29 to stop its propeller.”

Paradoxically, she died partly because she was a workaholic as well as a party animal. Heroin left her fresher for rehearsals the next day than booze ! did, and being up for rehearsal was essential to Joplin. Again, contrary to myth, each Joplin shriek and growl was carefully practiced and painstakingly recorded. “She’d come up with those things spontaneously,” says Andrew, “and then get them down cold, so in the studio she could go, ‘Okay, here’s No. 57’ !”

Like anyone on heroin, she was conning herself. Despite her growing artistry, her life was a mess. Her fiance, Seth Morgan, had smashed up his motorcycle with another girl (he died on a cycle in 1990). The night Joplin OD’d he was playing strip billiards in Frisco.

Had she lived, which side would have prevailed: the banshee glimpsed in Ellis Amburn’s seamy new bio, Pearl, or the dear heart in her sister Laura Joplin’s new upbeat, often funny book, Love, Janis? (When their mom was shocked by a nipple-revealing poster of Joplin, recounts Laura, Janis stammered, “It hardly shows, Mother.”) Andrew, who’s working on his own book, says that “she would have transcended her hot-mama phase. It would’ve been like-I don’t want to say Streisand, though her Streisand and Joan Baez imitations were perfect. She wouldn’t have abandoned her roots thing, but definitely broadened it.” As it was, her last recording was a gag birthday gift for John Lennon, an old Roy Rogers-Dale Evans ditty: “Happy trails to you, until we meet again…”