Wild shouts over a rock-hard drone, massive washes of sound which come to a halt as abrupt as a precipice. Welcome to the splendour of Lab singing - named after the province of Laberia - which is probably the oldest form of polyphony in existence. Some people think this is what Homer would have listened to nearly 3,000 years ago.

Laberia’s port city of Vlora has a terrible reputation these days as the smuggling capital of the world, with guns, drugs, and dangerously overloaded boatfuls of people. But it’s also the cradle for this extraordinary music, which people have sung all their lives. And it’s thanks to the repressive regime of Enver Hoxha, which maintained close ties with China but kept the rest of the world at bay, that this music still survives.

For while the tunes are changeless, the words are constantly mutating: in pre-literate villages, these Lab songs performed the function of newspapers, reporting and commenting on events as they occurred. One song which my group sang told the terrible tale of the boatful of emigrants which sank three years ago outside the Italian port of Otranto with the loss of 95 lives.

The world-wide march of Western pop has now reached Albania, but these farm-workers are fiercely defending their musical heritage. It helps that its structures are rigorously codified, with each of the four parts allotted its own particular function; they tell me that the drone must be so hard and impermeable “that not even a bullet can pierce it”.

They would love to tour to Britain, but as they even have trouble raising bus fares to their own capital, Tirana, we must make do with CDs. For the purest Lab singing, get Albanie: Polyphonies vocales du pays Lab (Inedit 260065), and to set this music in its national context listen to Music from Albania (Rounder CD5151).