Vulnerability and seduction -- oh, Sondre

At age 21, Norwegian singer-songwriter Sondre Lerche has just released one of the most mature and sophisticated pop-rock albums of the year. That makes you wonder: What will this young man be up to when he’s 30?

Lerche, who looks like a precocious 16-year-old, was in fine form Sunday at the Troubadour -- his first local show -- backed by a rollicking trio of fellow Norwegians named the Faces Down.

Combining songs from his 2002 debut and this year’s vastly superior “Two Way Monologue,” Lerche proved that his gift for pop craftsmanship transcends the limits of the recording studio. Sunday’s joyful performance combined the harmonic savoir-faire of a Burt Bacharach with the melodic exuberance of the Beach Boys, while at the same time replacing the new album’s baroque instrumentation with a vibrant touch of rock ‘n’ roll energy. Lerche’s only drawback lies in the lyrics. Because he writes in English, which is clearly not his native tongue, some of his musings on loneliness and romance sound awkward and disjointed.

But the occasional nonsensical rhyme was compensated for by deliciously unconventional phrasing and a richly textured voice that knows how to project vulnerability before breaking into a seductive falsetto.

Lerche’s oblique melodic sense has drawn comparison to the bossa nova. But there’s something inherently Scandinavian in melancholy vignettes such as “Stupid Memory” and “It’s Too Late” -- the kind of sunny, wistful ambience that informs most pop acts from the region, from ABBA to a-ha.

Whenever he addressed the capacity audience, the singer made up for his broken English with self-deprecating wit. The songs themselves confirmed him as one of the most talented new names in contemporary pop.