It is a contemporary piece by a composer who lives reclusively in Poland and until recently was just a name even to specialists. It is played by the London Sinfonietta, a group which for a quarter of a century has championed the most demanding and esoteric new music. Just the sort of thing, you would say, for one of those chilly concerts attended by six publishers, three fellow composers, two critics, and the very tall man in glasses who works in financial services and goes to everything.
Whether the seasonal rise of Henryk Gorecki's Symphony No 3 has anything to do with being on the sound track of the film Police, starring Gerard Depardieu and televised just before Christmas, is not clear. The record was already selling well and the piece has had a cult following for years. This is an extreme example of the apparently unstoppable spread of a taste for classical music that has seen opera stars opening sports tournaments, symphony orchestras travelling the globe like superstars, and music by Sir Harrison Birtwistle or Mark-Anthony Turnage on CD singles.
How has it happened? Is it the manipulation of ever larger markets by multinational commercial interests? A substitute for religion, or at least for a declining Christianity, in uneasy times? Optimists talk of the success of universal education. True music lovers see it as the arrival of the inevitable.
As for the internationalism, it was always there. The French have venerated Beethoven and the British have studied Bach. We have welcomed Haydn and Mendelssohn, Italian opera singers and American pianists, Indian players of the sitar and Indonesian exponents of the gamelan. Records and television are only catching up.
In terms of history, the crucial step was taken when classical music emerged from being the exclusive property of courts and aristocratic patrons and became available in public concerts. By the nineteenth century it was an accepted part of middle-class life. Once international mass travel became an economic possibility, whole orchestras took to the road. Many now spend a quarter of the year away from home. The beginnings of intercultural penetration are there, too. Japan is only the most exposed example. Many Asian countries have well-known nationals working in Western classical music, and their own musical traditions have acquired a following in Europe and America. Africa, where decolonisation has been slower, is still relatively marginalised, although African techniques, especially from drum music, have been appropriated by composers in the West, such as Steve Reich and Philip Glass.
And what Western classical music is the world performing and listening to? In the mid-twentieth century the 'popular classics' consisted of well-known orchestral works and some solo music, especially for piano. That is still the core. Until recently it seemed to be a closed repertoire. Since the 1960s it has expanded with the revival of period instruments and performing styles. In the last decade the question of performing styles has moved into the core itself.
Mozart and Haydn symphonies are less often played by the vast orchestras that developed to play the romantic works of the nineteenth century. Instead they, like Bach and Handel before them, have become the province of smaller specialist groups, lighter in tone, using the kind of instruments for which the music was written rather than the more sophisticated ones that have developed since.
Several other growth areas can be located. There has been an unexpected boom in string quartet concerts. The cause is the number of fine string players who are emerging from the colleges and conservatories and forming quartets to explore the music that has always been closest to the musicians' hearts.
Another unpredictable trend has been the revival of the song recital. Two decades ago this seemed a faded and decaying vestige of the era of salons and drawing-rooms. The repertoire was kept alive by devotees such as the London-based Songmakers' Almanac, who presented it in the context of entertaining explorations of the composers' lives and times, using several young singers in alternation during an evening.
But there is a buzz again around the traditional, single-singer format. It has followed from the opera boom: more singers have their followers; the classically trained voice itself seems to have a new public appeal, maybe fashionable, but still real; a generation of performers and listeners is discovering the treasury of songs that had been neglected.
The opera boom itself is the best- known musical upsurge of the present day. But the shock of very recent times has been the rediscovery of the new. Gorecki's Third Symphony is not an isolated occurrence. Composers and contemporary music groups have been finding an audience they have not had for most of this century. What has also been changing is creative musicians' attitude to their calling.
For decades, new music has been growing ever further from the experience of most professionals, let alone the public. So advanced are many of the front-line techniques that they have, in effect, become a university research speciality instead of a living musical skill. For composers to establish themselves, at least among their peers, they have had little option but to learn the prevailing ways of doing things.
There have always been a handful who broke with this tradition. But until now there were not enough for the music establishment to have to take them seriously. Even now, most of the new music you hear in concerts is, for the untrained, difficult to come to terms with. That is not a fault in itself but it does make a convenient smokescreen for mediocrity.
The ones who are 'getting across' include minimalists, melodists, and religious mystics. There is bound to be some reactionary opportunism: it blends in with currents of cultural retrenchment sweeping the West as wider values are felt to be under threat. The one thing for musical optimists to seize on is that performers and listeners are approaching Tavener and Part, Adams and Glass, MacMillan and Gorecki, with enthusiasm or energy or love.
What will come next? A lot depends on renewal. If the re-emergence of the new on a large scale is a passing vogue, then classical music seems set to become part of the international heritage business. There will be a polarity between well-established, historical music for large audiences, and small-scale, local, exploratory music which is in touch with some kind of living culture.
The obvious source of renewal now seems to be music from other countries' traditions: popular music is leading the way, but there are signs of interaction among more formal composers too. A classical or high-art version of 'world music' might be the vision to inspire many. But when the world is more concerned with closing doors than opening them, it will take courage.