Classical: Austerity to raise the hairs on the back of your neck

NOT SO long ago, a concert of Estonian religious music would have almost certainly guaranteed empty halls. But this week's three-stop tour by the Estonian Philharmonic Chamber Choir and Tallin Chamber Orchestra under To-nu Kaljuste, with music by Erkki-Sven Tuur and Arvo Part, quickly sold out the vast interior of Durham Cathedral, packed out Huddersfield Town Hall, and saw a large queue of people who were waiting for returns outside the Queen Elizabeth Hall in London.

Arvo Part, now 53, has become something of a New Age icon, the plain figures of his "mystic minimalism" chiming well with the body of taste that has reacted against the excesses of Modernism, as indeed Part turned from his own earlier serialism.

Tuur, who was born in 1959, seems to be evolving towards the same ecstatic spirituality. His brief Passion for strings (1993), begins with simple phrases, low in cellos and basses, but then grows more and more animated as folk-like fragments gradually lift the focal point of the texture. The music, whose modal contours give it an ageless quality, is intensely beautiful and does not seem to resist the onset of dissonance in the first violins: on its first encounter with this sign of ugliness, it dies away in pained silence.

Tuur's Requiem (1994) inhabits the same austerely ecstatic soundworld. Again, it grows from an opening low in the chorus, the strings weaving increasingly frantic commentary around the vocal lines as they move up to the first climax at "Tuba mirum", with the piano now adding a manic commentary and the sopranos and mezzos interjecting a few brief shrieks that recall the shamanistic music of his countryman, Veljo Tormis - this being the first time that this has sounded so explicitly Estonian.

The choir outlines a dislocated chorale before silence suddenly crashes in, and the solo soprano movingly intones the "Recordare". The choir slowly re-establishes the onward movement, ignoring the piano which suggests that one of Messiaen's exotic birds had perched on Tuur's score. Again, a dip into calm growth as the music moves towards the great cry of "Requiem eternam" that crowns the whole work; it fades to nothing and a single triangle stroke kisses it farewell.

Some of Arvo Part's music seems to re-stir the soup: instead of evolving, his style is simply re-applied to the next piece. The result is unfailingly beautiful, but one can sometimes have the feeling of having been here before as in his Trisagion (for strings) of 1992/95.

His Litany of 1994 is much more impressive. An English setting of 24 short prayers of St John Chrysostom, for solo quartet (here, the pure- toned Hilliard Ensemble), chorus and chamber orchestra, it builds very carefully: moving down the solo voices (with answering chorus) one by one, then two by two, then three and four, at which point choir and orchestra are allowed their first climax.

All the while, the music remains as plain and affecting as a hermit's cell. Though Part allows the chorus more freedom of action in the second half, he is still keeping his powder dry. Then the accumulated energy is released in a thrilling climax as the text calls for God to do His will, the music ringing and swinging in exultant phrases that the hairs on the nape of your neck on end. Finally, a gentle epilogue lays it all to rest.