A half- dozen albums into his career, Main man Robert Hampson (sans- Scott Dawson since the summer of 1996) proves he's evolving. Unlike better known ambient artists like µ-Ziq and the Orb that taint their organic and otherworldly atmospherics with commercially viable dance beats, Main remains loyal to Brian Eno's vision of ambient music as sonic wallpaper. One catch: you'd better like your wallpaper cobwebby, yellowed, and peeling from the corners.

Firmament III could be the soundtrack to your next Halloween party. The ominous footsteps and howling wind, the abandoned mansion with creaking doors, the axe murderer in the shadows-- all of these nightmarish cliches are here. Such environmental soundscapes will be nothing new to players of video games like "Castlevania" or "Nightmare Creatures." Still, that Hampson produces this haze of noise from his guitar, and that all five of the tracks occasion a visceral (but not emotional) response, is reason enough to commend Main for such esoteric experimentation.

Like most ambient music, Firmament III is difficult to appreciate on a "casual listening" basis. To become truly engaged you'll have to either turn out the lights and engross yourself in 39 minutes of bad karma, or conversely put the album out of your mind so that it effects you at a subconscious level. (Drugs probably work, too.) Either way, frequent listening is likely to result in delusional episodes, fits of maniacal laughter, and generally bad behavior.

-Zach Hammerman