HUDSON, N.Y.

As the band gets smaller, its musical vision seems to expand. Rhode Island-based band Brown Bird had beefed up to quintet size (after a stretch as a trio) before paring to its current form as a duo. Earlier recordings were more in the tradition of American folk, but influences from Eastern Europe informed the haunted, acoustic sound on 2011 album "Salt for Salt," recorded by the duo of Dave Lamb and MorganEve Swain.

Now, gaining momentum and acclaim, the two are gearing up for an April release of their second album as a duo, which they say will include influences from Middle Eastern music as well as metal and even psychedelic rock. Notably, it'll also feature electric guitar and bass, and concentrate on faster tempi.

"I think in the beginning stages of the band I was definitely focused pretty heavily on a very small portion of my influences in the writing process, and over time we've both been trying to incorporate more of what we love into the music that we create," Lamb said in a telephone interview from home. "When you have a larger group, for us it felt like we had to stick within certain parameters. But we have a lot of interests in common and we both have the kind of mindset where we feel very free to explore all those influences and see where they take us."

Brown Bird plays Helsinki Hudson on Saturday.

Lamb, the band's founder, plays acoustic guitar and foot percussion and is the primary vocalist. Swain contributes violin, cello and acoustic bass. The music sounds rooted in American blues and folk, with an affinity for dance rhythms from around the world. They've cited influences from 1960s-era Pakistani pop to noise rock and the music of Greece, though not all of that is evident on first listen.

Some have likened the sound to that of

Iron and Wine and Bon Iver, though Swain has quipped that this comparison has more to due with Lamb's prodigious beard than the music. Lyrically, Brown Bird's songs describe a sepia-toned landscape filled with boats, storms and the fury of divine judgment. There can be a bit of an "American Gothic" feel to photos of the two.

Though Lamb has the requisite background as a record store clerk to help explain his penchant for name-checking a bewildering variety of musical types, his time working in a boatyard, and other grueling day jobs, helps ground the work in something other than the back-to-the-land movement popular now among urban hipsters.

Lamb and Swain quit their day jobs in 2011, the year they also played the main stage of the Newport Folk Festival and saw the band gaining momentum after years of working below the commercial radar.

"When we first quit our jobs we didn't have a booking agent, we didn't have a manager. So it was a little bit of jumping off into the unknown. But we felt like there was momentum there," Lamb recalls.

Still, it's possible to catch Brown Bird in improbably intimate settings, given its growing profile; the band played the Brickhouse in Housatonic last month and has visited the Dream Away Lodge as well.

The upcoming record, called "Fits Of Reason," reflects Brown Bird's experiences touring in its current lineup as well as the two musicians' growing chops and interplay, Lamb says.

"I think the songwriting reflects a little bit more of the upbeat tempos that we've been playing our songs at in the live setting, and also a little bit more focus on intricate arrangements and on musicianship in general. There are some songs that are definitely more involved and definitely harder for me to play."

Based on its description, the next record is likely to pose a challenge to fans who liked Brown Bird's acoustic balance just fine. But the progression is natural, Lamb says.

"When you get into talking about what is American music or Americana, all the music we can claim as our own a melting pot of different cultures that have come together and come to this country under different circumstances, whether it be slavery and the blues or Appalachian music with a heavy influence from Ireland and Scotland," he says.

Brown Bird's music "definitely speaks to the American story, I think. I don't necessarily think about it that way all the time, but I definitely think that's very much a part of it."

In concert

Who: Brown Bird

When: 9 p.m. Saturday

Where: Club Helsinki Hudson, 405 Columbia St.,
Hudson, N.Y.

Tickets: $12 (advance);
$15 (day of show)

How: (518) 828-4800; helsinkihudson.com