The bass hits you first. You feel it deep in the pit of your stomach as it trembles from under your feet. Rumbling from the 8ft speakers, the sound undulates around the 700-odd clubbers who bob and weave to the incessant beats of Mr V and DJ Q. It might be 2am on a chilly Saturday evening in Sheffield, but most of the attendees of club Vibe's night Hanky Panky have at least another three hours left in them.
Their fingers grip cans of Red Stripe, bottles of WKD Blue and, occasionally, Moët. Some shout "brap" to applaud their favourite tracks; others enthusiastically splash Stella as though it were champagne. Sometimes the songs are purely instrumental; others feature high-pitched female vocals. Occasionally you'll hear speeded-up samples of tracks by grime star Dizzee Rascal, or R&B acts such as Toni Braxton and Leona Lewis. But they all have the same thing in common: bucketloads of bass.
"It gives you a great feeling in your tummy; it's really exciting," says 21-year-old Carla. "It's just vvvrrrbbbrrmmm," adds Gemma, 19. "That's the only way I can describe it." These teeth-rattling reverberations are known variously as bassline, bassline house or niche. Born about five years ago at the Niche nightclub in Sheffield, bassline is influenced by R&B, house and UK garage. Or, to be more specific, their sonic offshoots - known, variously, as 4/4, organ house, speed-garage, grime and 2-step. Darker, deeper, harder variations of dance music, these have long been popular with urban clubgoers - but bassline takes these rhythms further. "The thing that's big about it is that it's something everyone can relate to," says bassline producer DJ Q, who also hosts a weekly show on the BBC's digital black station 1Xtra. "It's brought back the excitement factor to clubbing."