“Olson has diversified the palette of sounds she’s working with — strings, pianos and tasteful drums enrich her songs.” — MJ Lawrence

Angel Olsen’s haunting voice was consistently fragile on 2012’s Half Way Home. Despite reaching the soaring falsetto of “Acrobat,” her airy vocals hung over minor-key arpeggios, yearning to be “safe … in the womb” or “deep in the nest of an endless dream,” as she sung “Safe in the Womb” Now, less than two years later, she leaves the womb boldly with Burn Your Fire For No Witness, her second album.

The album is a progression in numerous ways. At the simplest level, Olson has diversified the palette of sounds she’s working with — strings, pianos and tasteful drums enrich her songs, while production assistance from John Congleton (whose recent production credits include David Byrne & St. Vincent, Amanda Palmer and Bill Callahan) lends the compositions an ethereal flair. His presence in the recording might also be responsible for the deep and distinct character of the guitar on each track — it’s full-bodied in a way that stirs after multiple listens. Even on the minimalist ballad “Enemy,” her soft strums carry impressive emotional detail. “Enemy” sounds more like a duet between Olsen and her guitar than a simple singer-songwriter tune.

While her soulful croon on Half Way Home channeled Roy Orbison, Burn Your Fire is an unexpected turn toward post-punk. While the blaring guitar and propulsive drums on “Forgiven/Forgotten” convey the frustrated angst of her love-fueled doublespeak and songs like “Hi-Five” and “Stars” are blissfully fuzzed out, the album is more than a jaded pastiche of a ’60s folk sensibility. Instead, Olsen plays with a whole spectrum of folk-rock conventions, creating her own unique genre study while still offering friendly nods to other folk singers.

Album centerpiece “White Fire,” for example, resembles a distorted Leonard Cohen. In addition to the song’s subtle feedback, Cohen’s guitar-playing style, melodic phrasing and narrative technique are all on display. And the lyrics seem to be the clearest key to understanding the album as a whole: “If you’ve still got some light in you then go before it’s gone/ Burn your fire for no witness it’s the only way it’s done.” Olsen still sings as if she’s hurt, but she’s putting that inner fire to use — she sees it as a light.

And now she’s stronger, more resilient, more positive and even more rebellious than she was on Half Way Home. She lets in the light by asking, “Won’t you open a window sometime?/ What’s so wrong with the light?” In the past, she smoldered. Now, she shines.