The phrase that gets tossed around most often when publicists and writers talk about the music of Portland's Shook Twins is "quirky folk." It's a simple enough descriptor that's great to use when trying to convince skeptical friends to see the band in concert. But it's also a term that carries some negative connotations as well. "Quirky" isn't that far from "goofy," after all.

"I totally think it fits," says Laurie Shook, brushing away concerns that the label is painting her and her identical twin sister, Katelyn, into a corner. "I think 'quirky' just means the uncommon elements in our sound. You rarely hear beat boxing or chicken bocking or giant golden eggs in folk music."

Fair points, but it's not those little, unconventional touches that make Shook Twins' music worth paying attention to. The pair's 2011 album, Window, is modern folk done right. Unlike those of their contemporaries, the LP doesn't attempt to sound as if it were recorded in one afternoon around a single microphone. This is a modern band making a modern record that feels full-bodied, even if it relies on traditional folk instrumentation and storytelling. 

For all that is praiseworthy about Shook Twins' music, what really makes it shine are the sisters' tightly knit vocals. At times, you can't tell one voice from the other. It's a sound some call "sibling harmony," heard in the work of other kinfolk acts such as the Everly Brothers or Tegan and Sara. 

As you might imagine, it comes quite naturally to Shook Twins. "It's been like that since we were little kids," Laurie says. "Making up songs in the backseat of the car. There's even a video out there of us at age 5 with our mullets, dancing in the backyard and singing ‘Nothing Compares 2 U.’” 

The sisters didn't take music too seriously until they hit their 18th birthdays, when they started learning to play instruments and dabble in songwriting. There's more of a pop element in their first album, 2008's You Can Have the Rest, but those voices cut deep. They were an immediate success in their humble hometown of Sandpoint, Idaho. 

"Once we started playing," Laurie says, "we had a whole village of family members and friends that were behind us, supporting us the whole time. We toured out of Sandpoint for about two or three years, but we quickly became a big fish in a tiny town. Now, we're a medium-sized fish in a huge town."

The Shook sisters moved to Portland in early 2010 and have slowly added to their musical repertoire and reputation. They have a full backing band, including bassist Kyle Volkman, fiddler Anna Tivel and guitarist Niko Daoussis, and have become enmeshed with other local folksters like Nick Jaina and Mike Midlo, as well as jazz composer Ben Darwish, with whom they've formed the "fantasy folk-step" project Morning Ritual.

And Shook Twins have become known for their joyous live performances that include some unusual homemade instrumentation—including, yes, a giant golden egg. 

The egg was a gift of sorts, bestowed on the twins after seeing a gentleman in Seattle standing with it under his arm. They asked him about it, and he said he was told to take it, sign his name on it and then pass it along to someone else. The Shooks have turned it into a huge shaker by poking popcorn kernels into its hollow center through a small hole. Now, at every show, the egg gets a spot on center stage and is occasionally called on to provide percussion. The intention, of course, was for the twins to pass the egg along to a new owner at some point, but according to Laurie, it “will be given away in my will.” 

"We're still waiting for whoever started this whole thing with the egg to come forward and tell us how it came to be," she says. "But there aren't any rules to this thing. They didn't tell me when I had to give it away. So I think I’m going to hold on to it and let it fulfill its destiny.” 

SEE IT: Shook Twins play Wonder Ballroom, 128 N Russell St., with Lost Lander and Bike Thief, on Friday, March 29. 8 pm. $12 advance, $14 day of show. All ages.