Art: Classical: Tread softly, for you tread on my dreams

OXFORD FESTIVAL OF CONTEMPORARY MUSIC

"CROSS-OVER": NOT a nice word. "I am not a cross-over artist," the American soprano, Sylvia McNair, said on radio the other day. "I am a musician. And there's nothing I love so much as to sing a good song."

So Brahms and Gershwin, Schubert and Ives - it's all grist to the mill. But when it comes to modern music, it's not enough to cross over; you need a theme, and what better theme than Ireland: at once trendy and anguished, classless yet divisive?

Irish music surely can't be too difficult; and it packs them in, as we saw when two dozen punters were turned away from the Du Pre Music Building in St Hilda's on Saturday night.

The first half was essentially a prelude to the appearance of the splendid folk group Sin . But with the orchestra of St John's, Smith Square, and including a world premiere of a work by Dominic Muldowney, it couldn't have been better. His (six) "Irish Love Songs" were given by the mezzo Mary Carewe - a nonpareil Brecht/ Weill interpreter - with vocal panache and a delightful, snappy attack. As the composer said, "a trained voice, but an actor's perspective".

She was vibrant in "She moves through the fair" - how beautifully Muldowney absorbs and transforms the traditional melody - and moving also in a 19th- century Belfast poem ("My own Posalee"), which had a disturbing pre-echo of the Troubles.

After that, Gerald Barry's "Octet" appeared about as Irish as his mentor, Stockhausen. Our spirits lifted with a soprano, Anne O'Byrne, giving a radiant performance of Tavener's group of Yeats's poems, To a Child Dancing in the Wind. As always with Tavener, the Greek liturgy is not far in the background - especially in the harp harmonics linking each poem - and what could be more appropriate to Yeats's Sailing to Byzantium phase?

Yet most of these poems are much earlier; several of the greatest lines gained a new life from the soprano voice, accompanied only by flute, harp and viola. I shall not easily forget "For the world is more full of weeping than you can understand", or "Tread softly for you tread on my dreams".

I had not expected Yeats's elegiac, yet fresh, unsentimental tone to be sustained in the second half by Sin , but they did so admirably. All six players are virtuosi on at least two instruments; their founder, Stefn Hannigan, plays the traditional Irish goat-skin drum, the bodhran; many of these pieces began with its quiet, rhythmic pulse. A completely unexpected wealth of sound followed; wind (a remarkable collection of flutes and pipes) matching the two fiddles, played by Teresa Heanue and James O'Grady with a sort of crazy virtuosity often recalling Stephane Grappelli's jazz violin.

Much the most beautiful effect, however, was that of the uillean pipes (played under the arm). In O'Grady's hands, this produced an infinitely sad, haunting sound - exactly that, surely, required for the long lament in the third act of Tristan, usually played on the cor anglais but in fact specified by Wagner for an as yet unbuilt instrument of his own devising. It was marvellously matched with the voice of Taz, our third soprano of the evening; she has well focused tone and an excellent diction which frequently highlighted surprising lines - "I've crossed the sea-bed just to be with you". But she was most expressive in the traditional, wordless keening - at once despairing and consoling - which is, in fact, reminiscent of the bleaker moments in the plays of Yeats and Synge.

The only intruder on Sin 's platform was the piano, in this case a rather brash Yamaha. Its sleek, artificial sound seemed wretchedly at variance with the ancient instruments.