10,000 Hz Legend (2001)

These French alt Muzakers have always been aptly named; like air, their music can be breezy and refreshing even when you suspect there's nothing in it. The duo's fourth album, 10,000 Hz Legend, succumbs to their substance challenged side. The faux naive stance is merely irritating, the bubblegum track merely cute, the cheese rock quotient merely cheesy. Robotic voices so ruin the lovelorn lyric to ''How Does It Make You Feel?'' that a cameo by Beck (on the techno folk ''The Vagabond'') feels somber by comparison. As gorgeous as Air's array of keyboards can be, there's a thin line between ambient and aimless.