It was very nice of Laetitia Sadier to introduce each song that Stereolab played at Shinjuku Liquid Room Feb. 16. Though normally I find the practice distracting, in this case I was grateful, since the promoter hadn't provided a set list. (Concert reviewers like to give the impression that they know an artist's repertoire backward and forward, but usually we don't.) I was reminded of the first time I saw Talking Heads in 1978 and David Byrne's anal retentive thoroughness in making clear the name of each song before he played it.

Like the Heads, Stereolab favors form over other musical considerations. Normally, pop musicians who make a point of carving their songs out of marble and then buffing them to a brilliant luster either become automatons in concert, like former Stereolab member Sean O'Hagan's High Llamas, or avoid concerts altogether, like XTC.

But true pop overachievers treat each mode of expression as a distinct medium. The Heads' shows were never simply reiterations of songs. Tina Weymouth and Chris Frantz kept things steady and focused while Byrne freaked out, and it was this tension that gave their concerts the crackling immediacy the records lacked.

Likewise, Stereolab didn't play the songs from their newest album, "Cobra and Phases Group Play Voltage in the Milky Night," verbatim. They rebuilt them in such a way that you didn't need a Ph.D. in semiotics to get down.

The main difference is that Stereolab has no one like Byrne, who besides being a manic presence is a good singer. Sadier's relaxed Francophone drone is perfect for the group's lounge-pop prerogatives but it's hardly exceptional, especially in the lower registers where it tends to wobble. This was a problem during the first two female-centric songs, "Miss Modular" and "Infinity Girl," when the reverb seemed unusually strong. After the mix was fixed (Sadier, perhaps getting into her role as MC a little too responsibly: "This is what happens when you miss sound check"), the precision of the band's ideas was more apparent even if the playing itself wasn't all that precise. The musicians didn't always seem to be in perfect accord with the off-kilter, finger-snapping rhythms of "Op Hop Detonation," and the changes were frayed around the edges.

Even before he and Sadier formed the group in 1990, fearless leader Tim Gane bought the '50s idea that science would make life more convenient and fun, and the early albums combine punky irreverence with a dorky fascination for analog technology. Over the years, the punk element has been replaced by greater musical complexity, but the fun remains. They still use rhythm as a means of toughening up the wimpy styles they've chosen to reinvent, be they '60s French pops, bossa nova or TV theme songs.

You could hear the influence of Jim O'Rourke, the pope of Chicago's post-rock scene who produced "Cobra," in the expansive minimalism of "Free Design," with its 6/4 time signature and complex jazz-like layerings. But while the album cut sounds tentative, as if the musicians were afraid of getting it wrong, at the Liquid Room they attacked the song with the confidence of the Kronos Quartet.

Similarly, "Strobo Acceleration," with its lazy syncopated vocal lines and infectious dance beat, is rendered as fluff by O'Rourke while in concert it drove Sadier out of her shoulder-swinging insouciance into a wiggy demonstration of running in place (incidentally, a concert gesture that Byrne popularized).

Gane's scratchy guitar was clearly the foundation on which everything was constructed, but he preferred to hang back in the shadow of keyboardist Morgane Lhote. During the occasional detached coda, he would fiddle with various unseen electronic devices, as if he were the Wizard of Oz. Loud alien spaceship sounds bounced off the walls while a bowel-loosening hum undermined everyone's footing. It was a curious self-indulgence: The silliness of the noises didn't jibe with the determined seriousness that seemed to be involved in making them.

You could probably say the opposite about the lyrics, but since I don't usually listen to them I have no opinion about Sadier's Marxist sloganeering (except that her frail, Astrud Gilberto-like delivery makes her an unlikely soapbox lecturer). Still, Stereolab's music-making -- or concert-performing, for that matter -- is itself a kind of dialectic: First there's the lounge, and then there's the radical but nonetheless polite young artists who are determined to rearrange the furniture.

"Now we will play an old song for the geezers," guitarist Mary Hansen said before they did the last number, the title of which Sadier announced but which I couldn't make out. The song sounded remarkably like the Modern Lovers' "Roadrunner," which is about as far from the kind of music they play now as you can get without resorting to minor chords. It was, in fact, a very typical rock show ending: loud and fast and over quickly. Sometimes, the furniture is fine where it is.