Classical Birtwistle Retrospective Royal Festival Hall, SBC, London

It was an axiom of my old headmaster that music, whatever else it was, was not Bartk. Not Birtwistle, he would have added after Thursday's concert given by the Philharmonia Orchestra and Peter Eotvos at the Festival Hall, where works by both composers were included alongside a pair of Stravinskian classics. True, the Latin texts of the Symphony of Psalms might have comforted an old-fashioned schoolmaster. But the Symphonies of Wind Instruments and Bartk's Four Orchestral Pieces? Like Birtwistle's recent piano concerto, Antiphonics, played by Joanna MacGregor, they would have left him cold.

To confess, that was rather my own reaction on first hearing the new piece some years ago, so any reappraisal was an intriguing prospect for this final week of the South Bank's Birtwistle Retrospective. A CD release of Antiphonics proved strong on colour, but somehow missed the point. It was this second chance to know it in the flesh and to witness the dynamic exchanges between piano, wind and strings that finally brought the work to life. MacGregor coped brilliantly with the taxing solo part, and the music, for all the violence of its tuned percussion, drew not only furrowed brows but warm applause from the audience.

The experience had been matched the previous evening in the same venue with The Cry of Anubis, a tuba concertante that had sounded a shade too pale at its premiere 15 months ago. But on this occasion, with Franz Welser- Most conducting a rhythmically spot-on London Philharmonic Orchestra and soloist Owen Slade, the contours of the work, as neat as a jigsaw, fitted perfectly into the total scheme. Thus the series proved the truth of another, more acceptable axiom: that serious music needs at least a second attempt to begin to be understood.

But what help was on offer to listeners, pedagogues or others, for whom Birtwistle's music remains tough and unapproachable? On Wednesday, the palatable pill was some fruity woodwind playing in Mozart's "Haffner" Symphony and in the D minor piano concerto with Radu Lupu. Sweet in itself, the purity of Mozart's style also worked to remove those expectations we bring to a new piece, which, in Birtwistle's case, are so often disappointed because he draws so little from the recent past.

More generally, the way into the music was through the festival's theme of "secret theatre", which, even in those pieces least remote from the standard genres, meant something intrinsic to the text, not external and applied. The closest the week came to live theatrical action was on Monday in the subtle flow of attention between the Arditti String Quartet, the Capricorn Ensemble, conductor Lionel Friend, and Claron McFadden, all onstage at the Queen Elizabeth Hall in the premiere of Pulse Shadows. Conor Murphy's designs enhanced the dramatic potential of these Paul Celan settings for soprano, extended by instrumental interludes into an hour- long cycle. The poetry inspired delicate images that belied the composer's reputation for brutality. Reflecting past successes, they looked positively to the future as well.