Röyksopp

Röyksopp’s debut disc, Melody A.M. , soundtracked 2002’s hippest scenester seductions and drug-aided epiphanies. The Understanding starts in the same vein, with placid piano and a gentle percussive pulse, but then it turns the beat around, disco-style. Like party-planning professionals, Röyksopp has created a checklist of celebration essentials. Bop-gun bloops, quick-click drums, hand claps, an awestruck-choir effect, synthesizer swells, a sampled dude yelling “yeah” — all these elements appear during its up-tempo numbers. The Norwegian duo enhances its own airy vocals with supplemental singers: Chelonis R. Jones adds R&B flava, Kate Havnevik wails in dance-diva fashion and Karin Dreijer describes “flashlights and explosions” with a wide-eyed warble. The record’s centerpiece — or nadir, depending on the listener’s tolerance for excess — is “Alpha Male,” which sprawls like a ’70s prog suite. Opening with an ambient yawn and keyboard-generated horn fanfare, the track evolves into a techno thumper. It plays like a single-song career study, merging the group’s somnolent origins with its groove-driven present, and the contrast flatters the latter. Röyksopp’s chill-out approach has its charms, but its fast-paced material is a lot more fun.