In Lisbon, Portugal, Julianna Barwick was walking through a train station underpass on her way to the grocery store. She'd walked the path a couple times before, and occasionally she'd sing as she walked through the pass because she thought her voice sounded pretty good in there. One day she busted out her iPhone and recorded herself singing, just to see if the recording would sound okay, too. It did. She liked the recording enough to make it the vocal part in "St. Apolonia," the first song on her latest album, Will, which washes ashore tomorrow on Dead Oceans records. (You can still stream the whole thing on NPR First Listen.)

Though she does very little studio work, Barwick does record in spaces more traditional than train underpasses—a friend's house in upstate New York, the Moog Factory's sound lab in Asheville, NC—but her records are textured with the resonances of earth's little hollows.

She makes a lot of different kinds of sounds in those hollows. Sometimes she sounds like she's calling to you from across a field, sometimes like she's wailing from the top of a crow's nest, sometimes like she's an angel choir singing in full glory at the rising of the goddamn sun. More often than not her lyrics suggest words rather than fully articulate them, like hearing a voice on the wind or a little conversation burbling up from the stream. She loops these syllables together with strings and synths and pianos to create gorgeous, occasionally unsettling, vocal-driven ambient music that turns whatever room you're in into a sonic cathedral.

Her music so often evokes natural imagery—both its beauty and its tooth and claw. For me, Will is set out on the ocean—pacific, tumultuous, a play of lights and darks, shafts of sun rays breaking through wall clouds.

This tone—and the introduction of synths—represents a departure for Barwick. On her previous album, Nepenthe, Barwick's voice swam mid-heaven in a wash of bright acoustic warmth. For a solid week in the summer of 2013 I thought that all there was to do in life was lie on my floor and bliss out to that record.

Her shift toward darkness and dynamics in Will made me fearful: Is everything okay, Julianna? So I called her up and asked her. "[laughing] I'm great. I'm doing fine," she said. "There were some dark moments during the making of this record, but I feel great now. I can’t wait to start this tour."

But what's the deal with those synths? What happened to the children's choir and the goddamn sun-rising- with-soaring-violins thing? "I just wanted to do something a little different," she said. "I wanted to explore synth sounds, some low-end stuff. It was an intentional move, for sure."

Barwick said she played the FORM Arcosanti festival that Hundred Waters put together last year. There was a Moog Sound Lab set up there, and the guys there asked if she'd film a demo of the Moog Mother-32 that came out at the time. She said sure. "They had to teach me how to use it," she said. "So I played a couple little things. Both of those things I came up with on the spot were what ended up becoming “Nebula” and “See/Know" on the record." When she got back to the Moog Sound Lab in Asheville, she recreated those sounds and recorded them for real.

If you want to take that deep breath you've been meaning to take for the last five years, go hear those sounds at Fremont Abbey next Tuesday.