The vibe outside the Master Shipwright’s House in Deptford is exceedingly chill. There’s a few people bobbing and swaying but mostly, despite the occasional drizzle, the crowd consists of small groups sprawled out on the grass with packets of crisps and cans of Red Stripe. A man with a broad lace ruff around his neck weaves his way through the picnickers, beaming. A pair of pre-teens have taken over the dance floor, swinging each other about the raised platform with wild abandon. ‘You alright out there?’ asks the DJ, Gin Resis’Dance, a member of last year’s Turner nominees Black Obsidian Sound System. ‘Lovin’ it…’ She cues up Carroll Thompson’s 1981 lovers rock classic ‘Hopelessly in Love’. The heavy lolling bassline pulses out of a pair of speaker towers, four fridge-sized cabinets to each one. A banner in front of the decks reads, ‘R3 Sound System. Resist. Reject. Revolt. Music is Resistance.’

I’m on the Lewisham Sound System trail, an afternoon of bass-heavy DJ sets across four sites all over Deptford, part of the month-long Rebel Music festival. There are groups here going back forty-five years, alongside younger collectives like B.O.S.S. The whole district feels like a festival, as people wander from system to system bearing ice cream cones and plastic pint pots. Teenagers and pensioners, Black and white, gay and straight all dance together, side by side. But the atmosphere at such events was not always quite so mellow. Speaking to the Lewisham Ledger back in 2018, Steve McCarthy (aka Soft Wax of the Deptford Dub Club) recalls a certain anxiety hanging over of the local blues parties of half a century ago. ‘Obviously if you were having a party you wanted people to come,’ he said, ‘but on the other hand you didn’t want to publicise it too widely. There was this threat—how will people react?’ Racist arson attacks were shockingly common. One day in January 1981, a fire at a house party in New Cross, just up the road from here, resulted in the deaths of thirteen Black teenagers. A fourteenth subsequently took his own life. No-one has ever been charged in connection with those deaths.

Linton Kwesi Johnson remembers the New Cross fire well. Speaking at the Albany, off Deptford Market, a few weeks before the Sound System Trail, he recalls the tragedy as the spark which set off ‘the most important year of the post-war Black experience in Britain.’ The failure of the police and judiciary to respond led immediately to the formation of the New Cross Massacre Action Committee led by John La Rose of Beacon Books. On 2 March, that group mobilised a crowd of 20,000 for the Black People’s Day of Action. Following the Metropolitan Police’s disastrous expansion of the racist ‘sus’ laws in April under the name Operation Swamp, the so-called Brixton Riots erupted in South London, soon to be taken up with uprisings in every major city in England. ‘It was a watershed,’ Johnson recalls. ‘After that, things slowly began to change.’

As a member of the Race Today Collective, Johnson was a key figure in the Black activist movement of the period. Tracks like ‘New Crass Massahkah’ would provide its soundtrack. ‘I wrote about what I was involved in and I was involved in those campaigns,’ he said at the Albany. ‘I was talking about the struggles of the Black working class in England.’ But despite millions of record sales, Johnson never saw himself as a musical artist. When Richard Branson (‘clueless’) offered him an eight album deal, he said no thanks. But with the help of legendary producer Dennis Bovell, Johnson learnt to transform his manner of reading poetry into a musical instrument in its own right. ‘I was speaking basslines,’ he said. ‘I wanted the words to approximate what a bassline would sound like in a reggae tune.’

For the Lewisham Sound System trail, Bovell and friends have taken over the Albany’s back garden. ‘This one goes out to all the politicians who try to F the people,’ shouts the DJ as he cues up a 7” of Capleton’s ‘Leaders Let The People Down’. The Glady Wax sound system towers over the booth, six huge loudspeakers strapped together. There’s a sculptural quality to these speaker stacks—the camo-wrapped bright orange ziggurat of Unit 137 booming across the Market Square, Lemon Lounge’s sixteen-speaker mountain in birch ply over at Creekside Artworks—which was emphasised by Black Obsidian Sound System’s installation for the Turner Prize show last year, a dark and noisy space dominated by the speakers at its centre relaying the voices of Black lesbian sound system operators of the 1980s. ‘Sound system to me means collective,’ one of them says. Rebel Music amply demonstrates Lewisham’s pivotal role in that collective history.