It takes a minute and a half of relatively restrained headbanging before the lavishly bearded Kushal Gaya launches himself into the crowd. He screams some indecipherable lines from the front row before clambering back onstage to whip his hair like a metaller. But there are no crunching guitars for him to mosh along to; Gaya's jerking in step with a pair of guttural saxophones; pogoing to the beat of two drummers. In the hippest pub in the hippest part of London (the Shacklewell Arms in Dalston), sweat drips from the ceiling and the crowd have their hands in the air like it's a rave. Someone contact the Mercury prize people: jazz just went bananas.

Our energetic punk-jazzers are Melt Yourself Down, the new project from Acoustic Ladyland mainman Pete Wareham. But, despite being named after an album by seminal jazz-punk James Chance (recently heard adding his atonal sax to the Primal Scream album), it's not a tag that sits easily.

"I don't know anything about that [punk] scene, and it's not really jazz at all," he says. "I'm not really thinking in terms of what genre it is or it isn't. It's just got a certain energy and it's good to play in rooms where the audience can give you that energy back."

It's certainly a world away from Wareham's time as a postgrad at the Guildhall School of Music. He reckons he's been splintering off from traditional jazz composition since 2004. "I was approaching things as a nerdy jazz musician. I got very into the theory and there came a point when I realised that it was leading the music and it should be the other way round. Since then it's been an attempt to get away from a lot of theoretical stuff."

Wareham – currently "listening to a lot of trap" – got the initial inspiration for Melt Yourself Down while DJing. "I played a tune by this guy called Ali Hassan Kuban called Habibi and everyone loved it, and I suddenly thought, 'Wow I really want to do this,'" he says. "That sound was just drums, percussion, horns, vocals and bass; I wanted those massive horn lines. I started listening to nubian [Egyptian/Sudanese] drumming, so all the songs are based on nubian rhythms; there's just an energy to that music that I love and I'm trying to tap into. And because the inspiration for the band came from DJing a party, I wanted the gigs to have that same party atmosphere, with everyone dancing."

So what of that stagediving frontman; what language is that he's shouting at us in? "He's from Mauritius so it's sort-of French," says Wareham. "But there's some Creole in there, and he makes his own language up as well. He manages to get in and out again without us having to make any sections longer. But we'd get in the crowd too if we had radio mics."

The year's best party band just jumped off a stage near you.

Melt Yourself Down are currently on tour; their album is out in the UK on Mon 17 Jun