IT HADN'T BEEN Annalisa Tornfelt's intent to put out a solo album. When she was invited last July to perform at one of Abbie Weisenbloom's famed house concerts, it had been years since she'd even performed as a solo act.

"I was so nervous to do the house concert," Tornfelt says inside her Southeast studio, where she teaches violin. "I practiced every day for the month leading up to it."

Tornfelt is well known as the vocalist and fiddle player for Black Prairie, the dark folk-bluegrass band she joined in 2007, with Jon Neufeld and four-fifths of the Decemberists. Before Black Prairie, she toured extensively with bluegrass group Bearfoot, but the songs she was writing didn't fit with the music they were playing. It wasn't until joining Black Prairie that Tornfelt was motivated to write new music.

"I'd thought Black Prairie was going to be an instrumental band," she says, "but Chris Funk encouraged me to bring my songs and sing." Of course, sharing most of your bandmates with an internationally acclaimed band has its share of drawbacks, especially when said band embarks on a worldwide tour. With the Decemberists on the road, Tornfelt was looking at up to two years at home in Portland, without plans to perform any music. This was when she was invited to play Weisenbloom's house concert.

Soon after that performance, she received an email from Mike Coykendall. He'd started something he was calling Tapes on Tuesday, recording musicians at his home on his eight-track tape recorder. Tornfelt went through the catalog of songs she'd written over the last 10 years, and wrote a handful of new ones. She made an appointment with Coykendall.

"I was scared," she says. "I practiced the whole set over and over, in the order I would record them. I just wanted to get the songs down and get a good recording. I wasn't thinking about releasing them."

She and Coykendall recorded 15 songs in eight hours. After being encouraged to release the songs as an album, Tornfelt launched a PledgeMusic campaign, inviting anyone who wished to send payment and a letter to her personal PO box, and she would reply with the finished record, a handwritten thank-you letter, and a signed glossy photo.

Tornfelt titled the album The Number 8, inspired by the reoccurrence of eights during the recording process: eight-track recorder, finished in eight hours, recorded during August, the eighth month. (There are also eight letters in Annalisa and Tornfelt, but this didn't come up in conversation.) The songs are simple and unadorned, accompanied only by her voice and her 1930s Arch Kraft guitar, named Black Beauty.

The Number 8's opening track, "Scared You're Gonna Leave," is a bright country-rockabilly tune, and Tornfelt admits she wrote it for Sallie Ford to sing, but never sent it to her. Some songs feel as though they could be potential Black Prairie demos, particularly the haunting "Nothingness to Me," and "Riddle Me This," on which she plays the traditional Swedish nyckelharpa. Other songs, such as "Starlighting"—co-written with Laura Veirs—or "Play a Game," have a lighter, Patsy Cline feel, while "Just for a Day," co-written with Neufeld, evokes the country jazz delicacy of Willie Nelson's Stardust. Tornfelt keeps black-and-white postcards of Patsy Cline and the Carter Family in her studio, and she likely kept these same postcards near her while recording. (The album, if purchased at a local record store, comes with a limited-edition postcard of Tornfelt.)

As the backing band for her album release show at Alberta Rose Theatre, Tornfelt enlisted a few local guys she was already very familiar with: her younger brother, Tyler, and her longtime friends, Ford Tennis and Jeff Munger, together known as Sallie Ford's former band, the Sound Outside. She'll have the boys with her again during her month-long Wednesday residency at LaurelThirst Public House in April.

But as for her future plans with this project, Tornfelt is allowing things to happen naturally—in much the same way the album came to be. "It's just me, so I don't need to plan too far in advance," she says. "I'm excited to see what happens."