THE FIRST THING you'll notice about Moms, the new Menomena album, is that it sounds like a Menomena album—huge, dynamic, intricate, heavy without being overly aggressive. The second thing you'll notice about Moms is that it's the work of a two-man band: Justin Harris and Danny Seim.

Menomena slimmed from trio to duo not long after the release of their 2010 album, Mines, when Brent Knopf left the group after a decade. One of the most musically democratic bands in Portland—much of their recent press has dwelled on the inter-band conflict between its members—Menomena had to reinvent itself without one of its three founding contributors.

"We didn't know how it was going to turn out," says Seim. "We both agreed pretty quickly that we wanted to keep the band going. We had some show obligations when Brent quit, and we got some other guys and we played the shows, and I really enjoyed playing the shows. So then we were like, well, okay, let's just see if we can do this. The overall spirit of it just felt like it was a new set of challenges—that now there's just two of us and we have to make something work. Not to paint Brent as the bad guy at all—I think just the dynamic of the three of us was the bad thing."

Seim and Harris didn't do all that much differently for Moms, although Seim says the record is one of the most collaborative things he's done with Harris, with whom he's been friends since high school. "We started out with this one just jamming together and recording ideas," Seim says, "still working heavily with loops and then going off into our separate worlds and fleshing them out. It's not like one of us ever presents the other with a full-on song, like, 'These are your parts, play them.' It's like we have this blank slate on the computer that we're constantly adding shit to and trying not to make it sound overstuffed and cluttered."

Menomena has expanded to a five-piece live band—with Paul Alcott, Matt Dabrowiak, and Holcombe Waller—to replicate Moms' very full sound, but apart from a small handful of guest appearances, Harris and Seim recorded virtually all of the album's parts themselves, playing what sounds like hundreds of overdubs and interlocking pieces.

"We talked early on about trying to write and record as the touring band," says Seim, "but Justin and I came to the conclusion to prove, even just to ourselves, that we could still make an album just with the two elements of Menomena that still remain... without making it like a Creedence Clearwater Revisited or something," he laughs. "Inviting a lot of other people would really water down the little things that people have come to know about Menomena, and we wanted to make sure at least two thirds of those elements still existed.

"That was kind of part of the challenge, too: Are we gonna have 10 songs that are sorely lacking Brent's input?" Seim continues. "We didn't really know what to expect. And in the end, we stopped worrying about that, and just tried to make the songs the best we could. Thankfully, we agreed on a lyrical theme, which we haven't ever really done in the past. That helped us get on the same page, and shaped these songs into, more or less, a collection that hopefully fits well together."

Seim's mother died when he was a teenager, while Harris' mother raised him single-handedly after his dad left (the band's current press photos include Seim's and Harris' fathers), and those themes of family run through all of Moms' songs. It's a universal theme that's rarely dealt with in rock music.

"It's us and Danzig at this point," says Seim.

The album's title came from Dan Attoe, who painted the album cover. "We were going to call the album something else, and he was like, 'Oh, you should just call it Moms. All these songs are about your mom.' It was kind of a joke, but then we were like, that's actually kind of cool."