“I wanted a project that sounded like the jumble that’s in my brain,” says the Bleachers leader.

Ever wonder what Bleachers’ acclaimed 2014 album Strange Desire would sound like if its 11 tracks had been performed by a colorful array of female vocalists? Wonder no more: on Monday (Sept. 28), Jack Antonoff’s solo project released Terrible Thrills Vol. 2, a free, all-female “re-imagining” of his RCA debut, featuring re-workings of Strange Desire tracks by Sara Bareilles, Charli XCX, Tinashe, Carly Rae Jepsen and others.

Antonoff tells Billboard that the idea behind Terrible Thrills Vol. 2 actually came to him six years ago — his old band Steel Train released the first volume of an all-female covers compilation. “I wanted a project that sounded like the jumble that’s in my brain,” he says. “I hear my songs being sung by females before I change them and make them into my voice. The whole heart of this idea is for people to hear the album the way I hear it in my head, reinterpreted by the artists who sort of inspired it to be written in the first place.”

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The Bleachers mastermind and Fun. member started working in earnest on Terrible Thrills Vol. 2 about a year ago, following the July 2014 release of Strange Desire (which has sold 119,000 copies to date, according to Nielsen Music). Dixie Chicks' Natalie Maines was the first artist to sign on to the “alternate universe” recording of the album, as Antonoff puts it, with her cover of album closer “Who I Want You To Love,” and Jepsen’s “Shadow” was the final track to make the cut.

“Lucius completely reinterpreted ‘Wake Me,’ and turned it into this entirely different song which blew my mind,” says Antonoff. As for the most surprising rendition of a Bleachers song, he says, “Tinashe doing ‘I Wanna Get Better’ — it’s a really personal song, and it was hard for me to imagine anyone else doing it, but stylistically her and I are so incredibly different that I was fascinated to hear what she’d do with it, and I completely loved it. It just felt like the different expression of a song that, to me, was so stamped in one way.”

Bleachers recently wrapped a co-headlining tour with Charli XCX that concluded with Antonoff’s inaugural Shadow of the City festival in Asbury Park, N.J. on Sept. 19. Antonoff has co-written songs with Bareilles and Taylor Swift, among others, in recent years, and although Fun. fans are clamoring for a follow-up to 2012’s Some Nights, the singer-songwriter’s focus remains squarely on his Bleachers project.

“I’m in the studio right now, and I’m well into the next Bleachers album,” says Antonoff. “I have my head down, fully working on that. I’m doing a couple things with other artists, but I’m just sort of peppering that in. I finally understand what I want the Bleachers album to sound like, so I’m fully focused there.”