Music: In Huddersfield, it helps if you shout

Huddersfield Contemporary Music Festival Various venues, Huddersfield The Beggar's Opera Wilton's Music Hall, London Chapelle du Roi Stationers' Hall, London

One of the joys of the Huddersfield Contemporary Music Festival is the discovery that, levelled by the rigours of a Yorkshire mill town in November, even the most mythic figures of the avant-garde are human like the rest of us. In past years I've spotted Stockhausen in the Co- op, Birtwistle in Boots and Arvo Part in M & S. This year, I regret to say, the spotting count was down. And the reason was a 1999 policy to avoid superstars in favour of the up and coming "Young Olympians", as the festival publicity calls them.

Sure, there was Brian Eno, in residence to hear a concert of his own "ambient" music: the sound equivalent of Sixties lava lamps. There was also the saintly Jonathan Harvey. But mostly the composers have been lesser-known - and lucky to be there because Huddersfield these days ranks among the world's most prominent platforms for new music. From small beginnings as a sideline of the local polytechnic, it has grown almost to the status of an experimental Edinburgh. And the experiments cover presentation as well as content.

One of the best things last weekend was something I'd call a piano recital, if that isn't too genteel a term for what you get in a performance by Joanna MacGregor. Gutsy and open-minded, she plays everything from Bach to John Cage; and she plays with no pause between the pieces. In one unbroken sweep that jolts your ears you realise that a plaintive piece of Dowland has just metamorphosed into Birtwistle at his most brutally mechanical. I don't say you learn much by this, and I wouldn't encourage Alfred Brendel to try it. But once in a while a smart slap in the face to normal concert manners does no harm. And though MacGregor's temperament and technique are better suited to new work than to mainstream repertory, the Bach Allemande that finished this performance (accompanied by video projections of a spaced-out woman in a shopping mall) was beautifully played and oddly affecting.

As, in its way, was the music of the trio of American composers associated with the racy mixed ensemble called the Bang on a Can Allstars. You know what you're about to get from David Lang, Julia Wolfe and Michael Gordon when the leader of the Allstars turns to the audience and says - as he did at Huddersfield - "We come from New York where you have to shout to be heard." The Allstars music does a lot of shouting as it stalks that glamorous but awkward territory where hard rock meets the non-commercial avant-garde. But Julia Wolfe was arguably the most arresting personality at Huddersfield this year and certainly the most disturbing - with Girlfriend, a piece in a separate concert by the ensemble Lontano which shudders through my system even as I think about it. It came with nothing in the way of printed explanation but was a 20-minute lament for mixed instruments overlaid with a recording of a car-crash that repeated endlessly and at horrific volume. Half film noir, half Damien Hirst, it was presumably confessional: a testament to a destructive love-life. But whatever lay behind it, the intensity was sheer, if sickening.

As always, the question with Huddersfield is what all this tells you about the state of New Music today. And what it tells you is diversity. No common ground or language. For some this is liberating, for others imprisoning. When every new piece has to invent its own ground rules, the process of composition becomes painfully slow and the result hard to absorb - which is why New Music is economically unviable and unloved at the box office.

The dominant mood of Broomhill Opera is radical chic, with small productions done by big names in exotic venues like the semi-derelict Wilton's Music Hall: a stunning 19th-century theatre-space, if cramped and lacking anything that you could call "backstage". It makes a perfect place for Broomhill's new Jonathan Miller production of The Beggar's Opera, which has been done simply but with a period-update to Dickensian London. And the sharpness of the Miller touch results in one of the less tiresome stagings of the piece I've seen. Not many of the cast can sing, but that's allowable in something written as a knockabout parody of grand opera.The performances are raunchy, bold: not merely in your face but in your lap (beware the front row). And Miller makes darker drama than usual by adopting a version of the finale that lets Macheath hang, with no reprieve. You don't exactly weep for him, because this Macheath isn't exactly dashing (he looks and sounds like Ken Livingstone). But you do weep for the injustice that lets one crook swing while a stageful of others survive.

The Beggar's Opera in itself, though, is a bore. Its 18th-century wit is leaden and its music mostly doggerel - which accounts for a long tradition of later composers tarting it up. Broomhill's tarting has been done by Jonathan Lloyd, with a commissioned score that's jokily ironic in a raspberry- blowing streetwise way. But as applied to these simple tunes, the invention is counterproductive. It sounds complicated but unfinished, with a sketchy thinness that gives no support to the voices. They need it.

There wasn't much acoustic support for the voices that sang in Stationers' Hall on Monday night. I'd never heard Chapelle du Roi before - a group of 12 young singers specialising in Renaissance music - and I can't believe I heard them at their best as they tried to float 16th-century Spanish counterpoint through such a dry space. They sang with muscle and vitality. And what they sang was fascinating: an imagined Vespers for St Cecilia, the patron saint of music on whose very day we were hearing it: 22 November.

No one knows why Cecilia gets the saintly music brief. She was martyred for reasons of chastity, which is not a musical virtue. And though her death was operatically extreme - she proved harder to kill than Rasputin - that hardly explains it either. But no matter: she's an inspiration. And this concert was part of a whole Ceciliatide festival which runs during November in Stationers' Hall and gets more inspired every year.

`The Beggar's Opera': Wilton's Music Hall, London E1 (0870 906 3739) to 18 Dec