The sounds are strangely familiar: a rustle, a snap, a slow fade into silence. But you were expecting something less strange, music to pace your work or pleasure. The book-like case of Matthew Herbert's Plat du Jour is awash in color, a tie-dye suitable for a T-shirt or scarf, what the more sober-minded dismiss as "eye candy." Despite the idiom that warns against judging a work by its cover, your experience tells you that they usually correspond. A soft-lit portrait of an earnest, bespectacled man playing an acoustic guitar is unlikely to adorn an album of Norwegian death metal or X-rated gangster rap. By rights, then, this record with the unabashedly pretty packaging should sound like a spring day, bright flowers studding a sweet-smelling field. And it does, in a way. Only the sounds you're hearing don't merely call such a pastoral vision to mind. They actually sound like something recorded in a pasture, documenting a relaxing picnic lunch in the park. These sounds sound, in other words, like the sort of thing people have in mind when they say, "It was like music to our ears," precisely because it isn't music they are hearing. If there is dissonance in listening to Plat du Jour, it comes less from the sounds themselves than from the anxiety stirred up by the difficulty of classifying them. What does this record record? Does it matter where the sounds come from? Is it music or not?

Matthew Herbert has been provoking questions of this sort since the beginning of his career. One of the most respected figures in the world of electronic popular music, where he is a highly sought after "remix" specialist, working with artists like Björk, REM, Yoko Ono, and Serge Gainsbourg, he has devoted much of his own output to experiments in sound collage. These projects owe as much to the Modernist avant-garde of movements like Futurism and Dada as they do to the dance floor. In his first project, Wishmountain, which he began while a student at England's Exeter University in 1992, Herbert used the sampling technique pioneered by hip-hop DJs to record and perform tracks comprised, not of the shards of 1970s soul and funk, but of soundbites of everyday life. When he created a new persona as Radio Boy in 1997, he redeployed this aesthetic strategy in a more extreme form. Under the rubric The Mechanics of Destruction, for example, he used sounds made by destroying various branded consumer items on stage, such as a McDonald's Big Mac, a can of Coca-Cola, and a pair of boxer shorts from The Gap.

Confronting Plat du Jour for the first time, a listener familiar with Herbert's history as a politically aware provocateur might reasonably wonder whether he has gone soft, since both its sounds and the abstract imagery on the cover are outwardly soothing in comparison with Radio Boy and even Wishmountain. Take the first track. It begins with low-volume ambient noises that are gradually overlaid with percolating rhythms, what sounds like someone moaning in ecstasy, and a peripatetic figure, resembling a vibraphone, in which the pitch seems to shift ever so slightly off true in order to create synthetic "blue" notes. Yet as busy as this layering might seem, it never becomes abrasive. It's not a stretch to imagine it as the bed for a cutting-edge television commercial or the soundtrack for shoppers at a hip furniture store. And then, five minutes in, the peripatetic figure comes to the fore, with only the faintest rhythm bubbling beneath it. Suddenly freed from sonic clutter, the track's shimmering essence is revealed to be exceedingly easy listening, a wave machine for the ears. It's so soft that you sink into it like a velour beanbag chair. The experience unsettles. Has Matthew Herbert sold his soul to the industry heavies that see music only as a "social lubricant"?

A look at that first track's title, "The Truncated Life of a Modern Industrialized Chicken," suggests that he hasn't. And the liner notes confirm as much: "Field recordings: 30,000 broiler chickens in one barn. 24,000 one minute old chicks in one room of a commercial hatchery. 40 free-range chickens in a coop. One of those chickens being killed for a local farmer's market and its feathers washed and plucked." At first, the relationship between this list and the track itself is unclear. Herbert could be mocking the way song credits are normally written. But as the text continues, it becomes clear that he is interested in something deeper than parody. "All melodies and chords are samples of eggs on pyrex bowls," he notes. "All live percussion is made from a dozen organic free-range eggs, egg boxes, and egg cups played with chopsticks," and "the bassline is a 'cheep' from a minute-old chick pitched down." Clearly, the track's superficial softness is built on harder truths.

There's no guarantee, of course, that the people who listen to Plat du Jour will read that far. In the era of the iPod, many listeners never even see the records from which their playlist is drawn. Desperate to combat this trend, record labels frequently pack as many extras as possible into their releases - DVDs, posters, lengthy essays - in the hope that this less-easily-copied content will convince consumers to pay for a record they can listen to for free. The beauty of Plat du Jour's presentation is both an excellent example of this strategy - few records lose more when they are reduced to MP3 files - and a reminder that these "extras" can serve a different purpose than shoring up the music industry's sandcastle. Indeed, the album radically undermines the distinction between what is "extra" and what is not, suggesting that supplementary materials such as the packaging, liner notes, and the artist's website are as integral to the project as the tracks themselves.

Still, Herbert recognizes that listeners who concentrate on the record itself may miss the point. "I really don't have a problem with how people listen to it. There's no right or wrong way." Even those who have no knowledge of where the sounds on that first track come from will still be hearing something strikingly different from what the major labels market. "That has always been part of my politics, to try to encourage people to listen to different sounds whether they want to or not." Plat du Jour's appealing appearance and relatively placid sonic texture serves as that sort of encouragement. If they make listeners comfortable, it is in order to leave them disturbed. "That's one of the political points on this record," Herbert notes, "how something can appear to be what it actually is not. For example, the first track kind of stops and is almost on the verge of being jazz, quite light, and that's the moment in the piece where you sit down and enjoy the meal." In other words, this is where those chickens listed on the liner notes come home to roost. "So it's supposed to sound slightly naïve. If it sounds peaceful, there's a reason for it, a politics to that presentation as well as to the sounds themselves." At some point, a thoughtful listener is going to realize that the album's picnic of sounds - most of the tracks have food or drink in the title - is no picnic.

The superficial sweetness of Plat du Jour is thus a trap for unsuspecting listeners, inspiring them to take a closer look and then revealing, like one of those photographs that shows all the microscopic creatures that crawl around on our outwardly clean bodies, that our pleasure frequently depends on not looking too closely. Herbert is as politically engaged as ever, maybe even more so. Because this time he is out to question not only the corporations that destroy the fabric of human-scaled communities, but the foundations of taste themselves. "If you're asking people to think differently about their food, then it seems to me logical that you would ask them to think differently about sound." He isn't interested in "trying to write songs about chickens with a guitar," because hearing the conventions of protest music will prevent us from hearing anything new. By making his listeners wonder how Plat du Jour was made, as well as what it means, Matthew Herbert forcefully demonstrates his conviction that the products we consume, from music to muffins, must not be considered separately from the process of making them. In the end, it is the means of production that mean the most.