ROCK / Velvet revolutionaries no longer underground: The godparents of grunge are back on form. Ben Thompson meets Sonic Youth

AS VETERAN New York art-noise iconoclasts go, Sonic Youth are pretty popular right now. 'We're still not, like, famous,' insists Thurston Moore, their absurdly fresh-faced singer and guitarist. But they have just broken the habit of a lifetime by having a hit single, and Moore and his wife Kim Gordon, the band's bassist and co-singer, are revered as hard-rocking godparents by a whole generation of young musicians.

It was not always thus. 'When we first came to Britain,' Moore says, 'people thought we were some kind of a joke because we were trying to create some kind of hysteria using only two guitars, bass and drums.' These tools might have been old- fashioned, but the way they used them wasn't: they beat the guitars with their fists, detuned them apparently at random and stuck drumsticks down the back to bend the strings. This produced not only an evil racket, but, occasionally, a lovely, pure, spacious noise with an affinity to free jazz.

Like many a deconstruction before it, this assault on traditional rock forms helped establish a new classicism, via Sonic Youth's influence on a new wave of American guitar bands. When Thurston, Kim and Co went jokily corporate in 1989, signing to the Geffen label (home of Guns N' Roses and Cher), they had no idea that they were paving the way for a velvet revolution in American rock, whereby the underground went overground more or less overnight, and 'grunge rock' ('What a horrible term' - Thurston) became flavour of the year.

This has been a mixed blessing. Sonic Youth's shadowy but helpful role in the rise and rise of proteges Nirvana seems to be getting more attention than their own music, which is ironic, because they have chosen this moment to release what is almost certainly their best album: a raucously incendiary and ultimately uplifting record called Dirty.

They seem commendably unfussed about all of this. People have always had trouble deciding where Sonic Youth fit in. 'You always had to be either 'hardcore' or 'arty' ', Moore says, 'which is kind of puerile.' These were two stools between which Sonic Youth fell rather neatly. Both Moore and his co-guitarist Lee Renaldo had served time in avant-garde composer Glenn Branca's guitar choir of the late Seventies. And yet much of the band's inspiration came from the energy of American hardcore pioneers Black Flag, the Minutemen and Minor Threat.

'It's really hard to explain how important this stuff was,' Moore continues. 'To people who weren't living and growing up in America at the time, it probably just sounds like rehashed punk rock, but in fact it was the first real grass roots, legitimate American youth-culture since the Sixties; a million bands all across the country that all had the same formula. It was very instant, and the musical style was over once it started; but it dissipated into a very large arena, and the whole alternative scene grew out of it.'

Sonic Youth have been that scene's claw-hammer intellectuals without portfolio for a long time, but they've never lost momentum or threatened to turn into Sonic Maturity. They are kept sharp by numerous side-lines, like Moore's recent collaboration with Richard Hell, Dim Stars ('a conceptual piece that got out of control'), and Kitten, the band Gordon shares with fellow New York noise-legend Julia Cafritz of Pussy Galore fame. On a bad night, they've always had it in them to be pretty depressing, coasting self-absorbed down a cul-de-sac of feedback. But at their best they are exhilarating - the sound of things being broken up and remade at the same time - Moore's voice breathlessly laconic through a howling gale of guitars, Gordon shouting over the bass/drum rumble.

They spoke to a generation for whom Charles Manson rather than John F Kennedy was, if not quite the spiritual father, at least the person who most clearly represented what it was to be American. This has now given way to something that looks uncannily like idealism. Dirty makes a series of unusually forthright statements, forsaking a tendency to vagueness and musical meandering. 'Swimsuit Issue', for example, deals with sexual harassment in the wake of the Clarence Thomas hearings. Moore's notes say simply: 'We believe Anita Hill', and the song itself snarls 'Don't touch my breast; I'm just working at my desk'. 'Youth Against Fascism' pays tribute to those who bang cans outside the White House in free-form protest.

The music gains momentum from these shows of commitment, and 'Self-Fulfillment' and 'Sugar Kane' are two of the most exciting songs Sonic Youth have made. But are the band worried that Dirty might be thought of as their election year protest album? 'Only when people ask us about it.'

'Dirty' (GED 24485) is out now. Sonic Youth are expected to play in Britain later in the year.

(Photograph omitted)