In retrospect, the drug-hazed guitar smashing of Kurt Cobain and ’90s Seattle grunge seems like the equivalent of pink bunny slippers compared to what his contemporaries in Norway were up to. Scandinavia’s coldest country made headlines last decade for its thriving second wave black metal scene—as bands like Mayhem and Gorgoroth drove concert-goers to frenzied bliss with wave after wave of shrieking vocals, aggressive tremolo-picking, and guitar-riffing distortion, some misguided fans went out to burn churches and commit savagely ritualistic murders, citing the music as an influence. When the smoke finally cleared, Europeans—especially the British press—were more than ready to swap out the electric guitars for acoustic ones; listeners ditched their earplugs and settled in for the lower-key, turn-of-the-millennium after-party. Dubbed the “Bergen Wave” for the explosion of ambient electronica and folk-pop bands in that city, the new musical landscape canvassed a variety of genres and sounds. One quality held it together, though: it was decidedly mellow.

Of all the groups to emerge from that movement, sweater-clad, skinny-white-boy duo Kings of Convenience—otherwise known as Erlend Øye and Eirik Glambek Bøe—have found the most commercial success. Critical acclaim up to this point has been well-deserved: their delicate guitar strumming, occasionally infused with piano, horns, and violin, channels the pared-down acoustics of Pink Moon-era Nick Drake and warm harmonizing of Simon & Garfunkel into gentle, unassumingly beautiful melodies. Øye, the Paul Simon of the pair, sings in a slightly accented baritone about girls he’s once known or wishes he had; Bøe backs him up with a softer vocal counterpoint and elegant instrumentals.

“Declaration of Dependence,” the band’s third album, comes after a five-year gap in their discography. That long wait makes its blandness all the more underwhelming. Despite the delay, the new album sounds like Øye and Bøe simply wandered into the studio with their guitars one balmy afternoon. While the songs are as tranquil (and drum-shy) as ever—though perhaps a wee bit sunnier, thanks to a hint of bossa nova influence—they’re effortless in a way that suggests lack of precision rather than artistic aptitude.

Though lacking any stand-out single, moments of beauty are flecked throughout. Three broken chords plink out a simple, reassuring repetition in lullaby-like opener “24-25.” A lovely seesawing violin ushers in one of the album’s relatively fuller tracks, “Peacetime Resistance.” And Øye’s voice haunts the skeletal structure of “My Ship Isn’t Pretty” with brooding lyrics like “The sky was the blankest sheet / We drew lines upon it / So our thoughts could meet / Through cables black and cold.”

Yet the album’s 13 tracks aren’t just instrumentally sparser than past material; put simply, they’re also just not as catchy. Part of the problem is that they fail to develop their austere plucking into any grander themes, as the best selections from previous albums have managed to do. On 2004’s “I’d Rather Dance With You,” still their most perfectly crafted pop song to date, a stair-stepping piano outro elevates a jaunty beat to perfection; on 2001’s “I Don’t Know What I Can Save You From,” a gorgeous, transcendental violin solo strikes up around the three-minute mark. Every song on “Declaration,” on the other hand, pleases in almost exactly the same register from beginning to end. Kings of Convenience has never aspired to the shimmering textural distortions or swirling build-up of similarly laid-back bands like Grizzly Bear; but here, the crystalline simplicity of their music is symmetric to a fault.

This featureless quality of the new album’s soundscape is especially bizarre given the experience the boys were racking up on hiatus. After releasing their two studio albums—“Quiet Is the New Loud” and “Riot on an Empty Street”—as well as a remix compilation featuring high-profile guest artists like Four Tet and Ladytron, the two friends parted ways for a few years to pursue other priorities. Øye packed his bottle-cap glasses and scruff aesthetic off to Berlin, where he turn-tabled, released a successful solo album, reworked old favorites into catchy dance tunes for Studio !K7’s DJ Kicks series, and recorded ’80s-influenced electro-pop with side project Whitest Boy Alive. Meanwhile, the more introverted Bøe played gigs with his own second band, Kommode, and spent time at home in Bergen with his wife. Their musical reunion this year—in Mexico, of all places—promised to synthesize their respective sensibilities into a more satisfying, cohesive whole than ever before.

Unfortunately, that didn’t happen. A more exciting collaboration may indeed still lie ahead, but it won’t be found here. “Declaration of Dependence” is not a bad album; its only offense is just how totally inoffensive it is. The album works as background music for calm browsing in a used bookstore, or light accompaniment to late-night conversation with a friend, but it fails to stand up to any sustained listening, When the post-reunion glow wears off, Kings of Convenience will need either more hooks or more complex ways to communicate the emotional intensity their vocals and lyrics suggest.

—Staff writer Jessica A. Sequeira can be reached at jsequeir@fas.harvard.edu.