he label release notes for Fourcolor's first album, Water Mirror, described this Japanese artist's work perfectly: "Extremely gradual music". That label applied to Keiichi Sugimoto's first album under the Fourcolor moniker, and it also applies to his second album, Air Curtain. This is delicate, slow to rise and slow to settle music, the kind that works best late at night, when the rest of the world is sleeping. It's subtle music, which means that most won't bother paying attention long enough to recognize its merits. But those who do will be rewarded.

Sugimoto's earlier work as part of two duos (Minamo and Fonica) focused largely around combining live instrumentation with digital signal processing in intricate, beautiful ways. His work as Fourcolor is no different, save that the focus is less on Morr Music-like digital melodies and more on slowly-developing guitar/DSP drones that sputter to life and continually transform in new and unexpected ways. Each of the work's seven tracks are grounded in a glacial drone that fills out the low ends of the sound spectrum, making room for a variety of pops, blips, and other guitar-digital fragments that make up the bulk of the melodies here. Structurally, each track begins slowly and then builds itself up, layer by layer, into a fully evolved, complex organism by the end.

My description makes this album sound a bit repetitive; that's not actually true, however. The individual tracks might share some similarities in structure and sound sources, but each work tells its own story. "2 Strings", for example, begins with slowly reverberating guitar notes that grow into a soft, droning shimmer. Other melodic lines hover in the background for a time, and then harsh static rumbles around and mixes with the drone. As the track moves along, the static, rumbles, guitar notes, and drones all mix together, with the drone slowly building and dominating the proceedings. Compare this to "Empty Sky 1", which begins with a warm drone and some DSP/guitar fragments that float along until the guitar fragments coalesce into an echoing melody. Both works use the same basic sound sources and employ similar techniques, but the end results are clearly different listening experiences. As a result, the album as a whole is neither repetitive nor boring.

Air Curtain is, however, a prototypical 12k release—and, remember, 12k's motto is "too minimal for its own good". Like Christopher Willits' Folding, and the Tea, Doron Sadja's A Piece of String, a Sunset, and Sogar's Apikal Blend, Fourcolor's work is for listeners who want a little bit more than just a good beat with their electronic music. If you're one of those people, then you'll enjoy this. What else is there to say?