Noise is a relative concept — for many, it is what interferes with what we'd prefer to hear. For others, noise is a means to an end, a catharsis, or an inverse of what's known as "harmony." The Who, Velvet Underground, and the Beatles pioneered the inspired use of noise in the context of rock, and its role has been growing ever since. Brooklyn threesome Enon's new disc, Grass Geysers . . . Carbon Clouds finds them maintaining the tradition in their own sweetly cacophonous way. Geysers is a hearty omelet of sweet pop melody, punk thrash, Nirvana-ish bash, and My Bloody Valentine fuzz, all liberally seasoned with bracing, spiky dissonances. Unlike many "noise" bands, Enon features a fine singer, Toko Yasuda, whose seductively girlish voice makes a dandy contrast to the band's rippling bass, jackhammer guitar, and queasy, belching synthesizer. Pick hit: the surging, impudently urgent "Colette," with its catchy vocal chorus, nifty guitar hook, and drums that sound like trash cans with firecrackers exploding inside. Groovy!