Janis Joplin wasn’t around when her second solo album, Pearl, was released in January 1971. She wasn’t around a few weeks later when it shot to No. 1, either. The singer had died of a heroin overdose on Oct. 4, 1970, while recording the sessions that would make up Pearl.

That unfortunate turn of events illuminates the album’s legacy, which stands as her most defining work. Cheap Thrills, the second LP she made with Big Brother and the Holding Company, made her a star, but Pearl is all Joplin, from the striking cover photo of the singer dressed like an 1880s saloon worker and grasping a drink to the handpicked songs, which included tailor-made Kris Kristofferson and Bobby Womack covers to a couple of originals.

In December 1968, the Texas-born Joplin left the San Francisco-based Big Brother after two psychedelic blues albums and a few months after Cheap Thrills hit No. 1. Less than a year later, she released her solo debut, I Got Dem Ol’ Kozmic Blues Again Mama!, with a bunch of studio vets, which she named the Kozmic Blues Band, helping out.

It’s a solid record, firmly rooted in the blues and R&B Joplin sang with Big Brother. But it’s also a bit tentative, as if Joplin wasn’t quite sure which direction she wanted to head now that she was calling the shots. By the next year, when she started putting together the songs that would end up on Pearl, she had a more clear vision.

She again worked with a new group, the Full Tilt Boogie Band, which accompanied her on a summer concert tour and during several promotional appearances, like her memorable stops on The Dick Cavett Show. More suited to Joplin’s natural sound — bluesy, soulful, twangy — and made up of Canadian musicians headed by session guitarist John Till, Full Tilt seemed like a perfect fit for Joplin, whose out-sized stage presence often overshadowed her collaborators.

Sessions for the album began in Los Angeles in early September 1970, with Doors producer Paul Rothchild behind the boards. Within a month, they had almost a dozen songs recorded, all approved by Joplin. On Oct. 1, she laid down an a cappella take of “Mercedes Benz,” a song she co-wrote. It would be the last number she ever recorded. Three days later she was dead at the age of 27.

By the end of 1970, nine tracks with Joplin vocals were chosen for the album. A 10th song, “Buried Alive in the Blues,” was a Full Tilt instrumental that Joplin never got around to recording a vocal for. The finished songs — including the opening “Move Over” (the only song on Pearl for which Joplin received a sole writing credit), “Cry Baby” (which just missed the Top 40 when released as a single in May), “Half Moon,” “Me and Bobby McGee” (which reached No. 1 for two weeks), “Mercedes Benz,” “Trust Me” and the closing “Get It While You Can” (which was released as a single in September) — are among Joplin’s all-time best.

Pearl quickly climbed to No. 1 and stayed there for nine weeks. All these years later, it remains her triumph. Freed from the shackles that somewhat held her back with Big Brother and the Holding Company (a band not nearly as powerful as its singer) and on I Got Dem Ol’ Kozmic Blues Again Mama! (outside expectations prevented her from declaring too much independence), Joplin soars on Pearl, whether spinning gospel with soul or flexing a bluesy muscle on sturdy rockers or giving her big voice a workout on everything from country to R&B. All these years later, it still sounds like a new beginning. Sadly, it didn’t turn out that way.