MUSIC / Playing the system: In Britain, buskers are lumped in with pigeons and beggars; nuisances to be moved on. In New York, they take them so seriously they even audition them. Naseem Khan reports

They must be the strangest auditions in the world. This is not a theatre, or a cosy night- club. This is New York's Grand Central Station, a byword for grandeur and public pomp. We are seated in the North Balcony, overlooking a mighty concourse and overhung by a gigantic barrel-shaped roof in which constellations faintly glitter. Far below, trains and passengers come and go. Up on the balcony, the auditionees look slightly sick.

These are the annual auditions for performers who want to play in the New York subway, and I am one of 10 judges. Our job is easier than it might have been: the Metropolitan Transportation Authority, which licenses the performers, has already screened the original 400 applicants. Left on the wide polished balcony is the cream.

Performing on the underground in Britain is a furtive affair, in which performers, beggars and pigeons are regularly linked together as nuisances to the system. It is not so in New York. There, the MTA's Arts For Transit programme reserves the prime sites (of which Grand Central is one) for the artists who get past the judges. The ones who fail are not forbidden to busk. They simply do not have access to the money-spinning sites. If they adhere to the basic rules - no amplifiers on platforms, no crowds, no panhandling - they can, in theory, busk where they want. And a survey has shown that New Yorkers overwhelmingly approve, not only of the live art but also of the visual arts with which Arts For Transit is attempting to spruce up a decaying system.

But the line between official buskers and the non-official 'freelances' is more fraught than it sounds. A few years back the MTA decided to ban the freelances: there was uproar. Hundreds of buskers and commuters filed legal charges, and the MTA wisely retreated. But the freelances still live tenuously, moved on by officious police who haven't absorbed the party line. So it makes sense to get a permit; the auditions this morning matter. The judges all know this, and are on the side of the buskers. Some of them - like Annette Taylor, reported to have a voice like Aretha Franklin - are official subway performers themselves.

So, at 9am, we get to work. The group Sons and Lovers stand before the judges' long table; five young men who look as if they've been chosen for diversity of style - crumpled Hawaiian bush shirt, shirt and tie, student jeans - but who come together in a tight, warm a cappella. They treat Grand Central like any other venue, swaying and swinging and beaming infectiously at each other. 'Upbeat,' writes the judge on my left.

Just when we get attuned to cheerfulness, Arts For Transit lobs us Alexander Noreleski, a poignant figure of a man - small and grey-haired - in his early sixties. Slightly pear-shaped, he is a conservative dresser, and carries his saxophone as if it was a brief-case that embarrassingly metamorphosed on his way over. A small Ukrainian pin nestles in his lapel. Noreleski plays his solo sax with the sober concentration of the loner; listening to his version of 'If I Were a Rich Man', you get the feeling that he is playing to cheer himself up. Undeniably it is style.

But if you don't fancy melancholy, then you should get off at Irina Zagornova's stop. There was no ignoring Irina. She heralded her entry on the scene with a sudden high yelp, whipping the judges out of their Noreleski reverie. 'Aieee]' she shrills and there she is, all curvy and bubbly in a long lilac dress. Blond curls escape roguishly from a Russian hat laden with jangly beads. Her voice is high and nasally resonant. Warbling and tap-dancing with merry abandon around her nameless accordion-playing partner, Irina has us all spellbound. But how, asks one judge, will passengers respond? After a hard day at the office, confronted with such merriment, might they be impelled to push the Russian songstress under the train? We are instructed not to pick acts that will irritate commuters.

Classical musicians are a safe bet. No one would want to hit Konstantin Nazarov, a haunted violinist with the smouldering and raddled looks of Nureyev. Then come the tap dancers and jugglers (who lose their balls - 'Part of the act,' they lie blithely), folk and jazz musicians, singers and a man with a wonderful self-invented instrument involving door bells, strings and movable frets.

Mostly, the performers are young, in casual part-time work, and looking for fame and fortune. 'It's a way to get out and know people,' said Austrian Kathy Breitner, panting after her tap routine. Who knows? That mythical producer might be on the down train. It happens. Such myths and half-myths are part of the image of New York. And it is perhaps no accident that so many of the performers auditioning were new immigrants, many from the former Soviet Union and still struggling with English. It is as if this were the new frontier: the mobile entry point.

Below, Grand Central's concourse offers them proof of how things can work. As I make my way down to the trains, I happen on Wendy Saivetz setting up her official pitch. A young, unassuming woman, dressed in a long-faded summer dress and trainers, Saivetz found she made enough on the system to give up her job as an executive head- hunter. It's a slow pitch, she warns, as she tunes up her guitar. I lean against a stone pillar and listen with sheer pleasure to her clear, pure voice and the traditional folk ballad. The curious stop. A woman with a fur coat starts to finger Saivetz's CDs for sale. Thirty people are now gathered round. You look at the faces and you see one uniting emotion - hunger.

One level below, Alice Tan Ridley, a broad- shouldered young black woman, is pitching to an equally attentive crowd. She's singing Whitney Houston, her face and body tight with emotion. There is sweat on her forehead and her hand grips the microphone intensely. In time with her, the crowd - mainly black - moves and sways. 'Right]' they cry softly as she blazes out the lyric 'No matter what you do to me, You can't take away my dignity]' Round and round the shabby spaces the sound rolls and reverberates.

'The idea is wonderful,' one of the judges says, 'because the subway is quite an inhuman place. Busking is an affirmation of art and humanity. And some of the people are quite extraordinary.' The streets of New York may no longer be paved with gold. But look below and you can certainly find platinum.

(Photographs omitted)