MUSIC / Short, sharp but not so shocking: Robert Maycock on the Platform summer new music festival

Times are tough for new music festivals. Even the high profile and higher energy of Joanna MacGregor's summer 'Platform' haven't shielded it from three years of struggle. Born from outrage and improvisation when the old-style Almeida Festival vanished, it kept up its momentum through 1992 only to face, now, a late loss of support from Collins Classics, MacGregor's record company. But it's still there, prodding away at the ingrown dourness of a scene that sometimes seems to pride itself on resisting appeal to outsiders. Result, on Wednesday at least: a modest-sized audience, but a young and vocal one for some fairly heavy stuff.

This year the novelties include double bills, audio-visuals by The Common Sense, and jazz. They bring their own problems, for by all accounts the jazzers have been wiping the floor with the others in terms of musical communication. Everything is boxed off: the concentrated and the free, the slick and the rebarbative. It's worth finding the courage to mix the boxes up a bit, if the response to Shiva Nova's latest London season (shared by straight, jazz and Indian musicians) is anything to go by. Scratch the surface of the Platform festivals and you still find conventional attitudes to contemporary music.

So Jane Chapman was able to sail obliviously through the lighting and video effects that surrounded her harpsichord on Wednesday, playing a sequence of modern soundbites as though she'd prefer to be communing with a few friends. It had to come over as a sequence: the screen images of detail on the instrument, beautiful in themselves, neatly bridged the gaps between pieces where everybody normally shuffles and coughs, while the dark auditorium stopped you reading what the music was. The bite-sized repertoire suited the audience - the shorter the piece, the louder the applause - and played to the strengths of the writing. Rapid changes of texture or frantic bursts of activity can overcome the harpsichord's inherent lack of sustaining power, so James Dillon's bristling Birl and Ligeti's classic Continuum were the high points.

Following on, a quartet of players from Ixion took a sparer attitude to presentation. Ixion is often a frustrating group because it seems to be on the verge of something really dangerous. It likes repertoire of the primal scream sort, programme notes about 'rough treatment', and a leathery look to the players' dress. But then it holds back from the implications, and hides its feelings decorously behind music stands - very proper and British.

At the heart of this set were two tiny pieces for solo viola. This doesn't necessarily have to be the most restrained of media, though it was here, and to the advantage of both works. Jonathan Harvey's Chant grew out of a hint of timeless drone, singing and touching the sky; Howard Skempton's Moto Perpetuo fidgeted at its rhythmic confines like a dancer condemned to move in everlasting circles. It wasn't the right context for longer pieces by Magnus Lindberg and Michael Finnissy, which outstayed their welcome. The surprise came last, when Andrew Toovey's Splice had striding piano, pulsing strings and jazzy bass clarinet on a short and witty collision course. It was a product of work on Toovey's opera Ubu, where caprices like this were lost in a swamp of schoolboy scatology. Bites do have their benefits.