This week, Somerville, Mass. is getting a taste of Iceland.Experimental rock group Mum, along with Sin Fang Bous (aka Sindri Mar Sigfusson of the rock band Seabear), will make a stop at the Somerville Theater tomorrow night on what will be Sigfusson's first trip to the U.S.

Though the two groups may not seem perfectly matched-the experimental instrumentation and gentle, whispery singing Mum is known for being somewhat far afield from the folksy sound of Sindri's band-Mum's most recent album and Sigfusson's solo album seem to converge stylistically. Unlike Mum's 2002 album Finally We Are No One and 2007's Go Go Smear the Poison Ivy, this year's Sing Along to Songs You Don't Know has a much poppier sound. Conversely, Sin Fang Bous's Clangour, released earlier this year, features more unusual instrumentation than many of his songs with Seabear.

Both bands discussed their evolving styles with the Justice. When asked what the other members of Seabear thought about Sigfusson's solo project, he said, "I think they like it. Soley is playing with me in the live Sin Fang band. We all have other music and art projects to keep us busy."

Mum has seen something of a revolving door of performers since the group formed in 1998. Founding member orvar _oreyjarson Smarason didn't think the grouping and regrouping of collaborators was a defining factor in its changing style. "Our friends and musicians have come and gone between every single album or tour we have ever made. People may think this is something new to us, but it is the way we have always done it. This makes me believe that change is probably an integral part of our creativity, but it could possibly be the other way around," he said.

As for the way the bands will sound tomorrow night, concertgoers can expect a fascinating show as Mum breaks out all the bells and whistles (literally) that make up its eccentric sound. Of their menagerie of instruments, Smarason said, "Lugging around a heap of instruments is a drag, especially at airports, when the check-in people give you the evil eye and demand a ransom for overweight. But we aren't just a simple guitar-bass-drums band, so we have to adapt, obviously. And after taking close to a ton of instruments by helicopter and boat to our lighthouse place [referring to the lighthouse on the northwest coast of Iceland where the group recorded Finally] a couple of times, other logistical problems seem very light in comparison."

While Mum will continue on to tour Europe after its North America tour ends on Nov. 7, Sigfusson is looking forward to working on new projects. "We just finished mixing the new Seabear album and that will come out early next year," he said. "I'm currently recording a new Sin Fang album that will also come out next year. I'm also very excited for a new unnamed band I'm in. We're writing the music for our first album these days."

Mum and Sin Fang Bous will appear Wednesday at 8 p.m. at the Somerville Theater in Davis Square. Tickets are $22.