For a day, Paris is City of Sounds

Once a year, at the summer solstice, the City of Lights is transformed into the City of Sounds.

For the space of 12 hours or so, as Paris celebrates its annual Fête de la Musique, musicians playing every style of music, from rap to Rimsky-Korsakov, take over squares, street corners, parks, and public buildings, turning the French capital into a polyphonic kaleidoscope of enthusiastic noise.

There was no escaping it on Tuesday, nor did the hundreds of thousands of Parisians strolling the streets on a balmy summer's evening want to escape it. Instead, they reveled in the variety, allowing themselves to be transported from continent to continent as they walked from block to block and discovered music from the four corners of the earth.

My fête started in the middle of the afternoon, when I came across a Brazilian combo playing samba by the river Seine under a suitably sweltering sun. Then I headed a few hundred yards to the giant Les Halles shopping mall, where a music- and bookstore was hosting a piano and saxophone duo playing cool jazz.

Half the fun of the Fête de la Musique, though, is coming across bands unexpectedly - ones not on the official program but who plant themselves wherever they can find a space. En route to the jazz I was distracted by four South American Indians, dressed in North American Indian feathers and leather fringes, playing Andean flute music over a techno background. They drew a curious crowd.

This was all a far cry from the first Fête, held in 1982, the inaugural year of President François Mitterrand's socialist government, when the Ministry of Culture handed out instructions on how to construct homemade instruments and encouraged people to play them in the street between 8:30 p.m. and 9:00 p.m. on June 21. Now most towns and cities around France, and even capitals around Europe, hold their own fêtes.

I had hoped to catch a band advertised as playing "convivial electrorock" just off the rue de Rivoli, but by early evening they were still at the "un, deux, trois, test" stage of setting up. So instead, around the corner I found a klezmer orchestra blocking the street as they played Eastern European Jewish dance music on clarinet, fiddle, and accordion.

Five hundred yards away I ran slap bang into the middle of a crowd clad almost exclusively in black, leaping up and down energetically to a deafening group playing music defined in the program as either "grindcore" or "powertrash." I did not stay to find out which.

I would have been welcome, though, however badly I stood out. The fête's magic lies in the way it breaks down barriers: musicians playing everything from Mozart to heavy metal appropriate a public space, and invite anyone who shows up to share it. The result is a refreshing cross-pollination of people who normally would not mix.

The most surreal example of barrier-breaking was a gospel choir, comprised almost exclusively of white people dressed in African robes, singing Congolese songs in the Lingala language. To cap it all, they were singing in the ruins of a Roman amphitheater, where gladiators once fought lions.

After an hour packed into a crowd enraptured by the infectiously danceable "rai" music of Algeria, it was time to go home. (I had imposed a midnight curfew on my two teenage sons, who had gone off to listen to hip-hop and techno at the Bastille.) But midnight is no time to go to bed at the Fête de la Musique.

Directly beneath my bedroom window, a collection of aging, potbellied rockers had set themselves up outside an Irish pub and surrendered themselves to their Eric Clapton fantasies. Sleep was out of the question, and I have a few Eric Clapton fantasies of my own, so I went back downstairs to join them.

At 1:00 a.m., the city noise ordinances came back into force. At ten past one, the lead guitarist played his final riff. At a quarter past one I was asleep. And dreaming of next year's fête.