The riots had a soundtrack.

In 1995, insolently young south Londoners Eddie Otchere and Andrew Green, as James T. Kirk and Two Fingers, published Junglist, a brilliant neglected text of London gnosis, backstreet Modernism, a strange riff on being young in the city and in thrall to the dance music of the time. Jungle, deep structured by beats, full of industrial blarings like the mating calls of old factories. London music conducted by aliens.

Sixteen years, generations and crossbreeds later, two descendant musics tussle for hegemony – dubstep and grime. The former is all wobbling bass, looped fuzzed samples, tight drums. It’s viralled fast into commercial cliché and star turns, uninteresting but for a few left-field experimenters, like the ’post-dubstep’ melancholy of London genius Burial. Tracks for those nightwalks.

Grime is the bratty, bolshy sibling. The riot music. Born out of London’s pirate radio scene, shouty vocals over frenetic beats. Indelibly London, saturated with the localism of the city itself. In grime, representing your area, sometimes down to your street, is key. Not overtly political music, for the most part, it is, though, to the horror of splenetic politicians, an angry one.

30 November. Shoreditch. We’re south of the White Cube gallery, in old streets embedded in folksong. Working-class once, now arts-gentrified, wedged full of subtle-fonted bar-signs, boutiques and hangouts. Downstairs at the club East Village, it’s the launch of Rival’s EP, Lord Rivz.

The music goes like an adrenalized heart. All the movements in the thundering dark hall, dancing, nodding, twitching in place, are stiff-limbed. Tune segues into tune that flaunts its discordance, its jerking rhythm: it’s ornery, a kind of anti-dance music, demanding you move but making you work to work it. There’s no aggro, not among the dancers, despite all the screwfaces, wincing like they hurt, making some noise when they hear classic tracks. And then the MCs step up, and there’s a surge for the decks. ‘Music,’ Dan Hancox shouts, ‘to storm the Treasury to.’

That’s the kind of joke can get a person closed down. Hancox is a writer on politics, on grime, on youth. We’re buffeted by what they called the soundtrack to the riots. Music of this austerity moment.

It’s exhausting, being smacked around by east London beats. We break from the club, stand outside near the smokers and enjoy the cold air. Hancox’s excitement ebbs. ‘It dampens the spirits a bit,’ he says. ’It’s about a third full?’

About a third, yes. There’s been a sustained campaign against grime from all establishment sides. Hancox mutters about form 696. The Met uses this notorious risk assessment paperwork in deciding to allow – or not to allow – musical events. Until 2008, almost unbelievably, its original wording ferreted ingenuously, ‘Is there a particular ethnic group attending? If “yes” please state group.’

Outrage. The wording changed, the targeting remained.

It was hard for Hancox to track down a night to go to at all.