In the name of the fado

Madredeus are big in Portugal. They draw on local traditions but set their own (very clear) musical agenda. So far, so admirable. But does the theory translate into practice?

While some music is like a manifesto for action, filled with a nervous energy that seems to pass from player to listener without pause for thought (one thinks, fondly, of punk and the Ramones), that of the Portuguese group Madredeus is more like a glorious stasis. Classical guitars strum in stately measures, occasionally interrupted by an impossibly pure female voice trilling away in a language most of us won't understand. True, nothing much happens, but it does so so decoratively that you are happy just to bask for a while in the charming vacuum. Appropriately for a group from Portugal, whose history is so bound up with Atlantic trade routes, listening to Madredeus is a bit like looking at the sea; one wave may be much the same as another, but the overall pattern is sufficient to make the experience both restful and diverting.

The experience is also remarkably popular. Since forming in Lisbon in 1985, Madredeus have released seven albums, each selling more than 500,000 copies (admittedly, many of them in Portugal, where their last album stayed in the Top 5 for five months). They also received the accolade of being chosen by Wim Wenders to provide the music for the film Lisbon Story, the director's project before his big hit of Buena Vista Social Club. Although the group are signed to EMI, the UK has so far remained rather slow to catch on, but Madredeus arrive here to play London's Royal Festival Hall tomorrow, in support of their just-released new album, Movimento.

Named after the Madre de Deus district of Lisbon where they came together, Madredeus is the brainchild of the composer and guitarist Pedro Ayres Magalhaes, who ­ however unlikely it might seem, and it does ­ used to play in a punk band. Indeed, it was partly this experience that led him to change direction and form the present group, which is explicitly dedicated to performing original repertoire in Portuguese. "There is a tendency to say that in order to become internationally successful you must sing in English," Magalhaes told me when we met in Paris last month. "But this was a struggle I had in my own country 10 years before Madredeus, with electric bands. When you hear a drum-kit and an electric guitar, the audience is already prepared to start hearing the vocal sung in English. You think you are creating original texts in your own language, but no one gives a damn what the singer is saying because it's so loud and everyone is dancing. I was a bit frustrated so I thought, no, I will take away these archetypes, take away the drum-kit and the electric guitar, and I will use traditional instruments and a very pure voice. And that is what we have done."

The way Magalhaes tells it, he assembled the elements of Madredeus according to a rigid programme. A marvellously florid intellectual with an impeccably melancholy face, who at 2pm had just emerged from his bed after a long night of lobster dinners and celebratory drinks following the previous night's concert at the Olympia, Magalhaes raps out the stages of his master-plan with a hauteur that cannot easily be interrupted. "In the beginning of this group, we have certain circumstances that may seem to you very vague but they are not vague," he says, pausing to light up a cigarette. "First, the group was made in the assumption that we are from Lisbon and the music of Lisbon is fado ­ music not to dance to but to listen ­ and the words are like a paradigm of how lyrics can be understood through the way they are sung. We are not going to use the old songs, or play old songs with new arrangements or different instruments; we are going to do our own songs and the girl will be singing, a classical guitar will be playing, along with a keyboard, which at that time was like a Casio or something."

The key ingredient, at least for the group's subsequent success, was the recruitment of Teresa Salgueiro as vocalist. "When we found this girl, we found what we could call a kind of traditional voice. It was pure, she was very young, and her voice was an archetype of the female voice in our country, so here already two traditions meet," says Magalhaes.

The other founding ideas were that they should be a travelling band, following the tradition of itinerant musicians who could arrive anywhere and begin to play with the minimum of fuss. "It was five musicians and the guitars," Magalhaes says. "We could fit in a station wagon with the instruments in the back. This was very important." Another precursor was the 19th-century Lisbon tradition of musical salons; chamber music concerts in people's homes. "I said that we would do recitals of poetry with our music, and the people would sit in silence. We wouldn't expect them to do anything, not even applaud. We will play one song, and another, and another, and that's it."

So there's the theory, but what about the practice? In concert at the Olympia, Madredeus were relentlessly tasteful. With the six members strung out across the stage like a widescreen family portrait, and all except Teresa sitting on stools as if they expected to be there for an awful long time, one song did indeed follow another, and another, and another, with little change of pace or emphasis. For me, the experience became increasingly unbearable. All the rough edges of fado seemed to have been sanded away, along with much of the bass and treble to the sound, leaving only a polite mid-range of endless guitar strumming, undifferentiated vocal trilling, and a background of rather cheesy synth-washes. It was like being slowly smothered in antique lace, and I couldn't help thinking, again, of the Ramones, who by this time would have played 50 songs and gone on to another gig, perhaps in Germany.

An hour or so went by, but there was still no sense of impending closure, nor of any restiveness from the adoring audience. As the rows at the Olympia are very close together and I was trapped in a particularly tight spot far from an aisle, I began to panic. After spending another three numbers staring fixedly at a Fire Exit sign, I took advantage of an unusually long round of applause to push past the end of my row and throw myself through the door.

Emerging into the half-light of what looked welcomingly like a deserted shopping centre, I punched the air in triumph. A taxi took me back to the hotel where I curled up in my room with Sky News and three cans of strong lager, deliriously happy to be spending a Saturday night in Paris in this way. It's not that Madredeus aren't wonderful of course, just that I think I prefer them on record, where you can turn them off. I've been playing the Ramones daily ever since.

Madredeus perform tomorrow evening at the Royal Festival Hall, London (020-7960 4242. 'Movimento' is out now on EMI