Two distinct characters are headlining tonight, though they're part of the same person. One is Sumach Ecks, whose whacked-out chat is as confounding as you get this side of a Goan ashram. The other is his alter-ego Gonjasufi, who is about to step on stage and reconfirm his status as one of the most progressive and originally boisterous artists today. But first, we're sitting backstage and the former is filling me in on his guide for life.

"Fuck the po. Fuck the Queen. Fuck Margaret Thatcher. They're all part of the same shit, g. They're devils - devil demonic shit, yeahhh..." It's pretty late already and not long till his set kicks off. Industrial-strength spliff in one hand, Sumach slouches back on his chair in the basement of Village Underground. His low rasp is barely audible through the fug of smoke as he rumbles on: "They say, yeah we're going to Mars 'cos the astroids comin', it's gonna hit Earth. I say fuck you man - you're gonna hit by the asteroid as you trying to get to Mars and leave the Earth...". I ask him if I'll be safe because I can't afford to go to Mars and he looks at me like I'm tripping.

Most of what comes out of Sumach is as cryptic and nonsensical as the fuzzed-out vocals he hollers at the crowd as Gonjasufi later that night. During the soundcheck he's buzzing - he bounces around and paces the full length of the venue, performing acrobatic handstands against the wall, squaring up to sound technicians. For someone who moonlights as a yoga instructor, he doesn't seem that chilled. Not right now anyway. Pre-gig nerves and a late-running soundcheck maybe, but he tells me that his flight to London that evening got him riled.

"We flew all the fuck over here - we flew and risked our lives on that plane, man," he says. "We drove from Cork to some airport and showed up just 20 minutes before the plane was due to take off. We were getting pressured and hassled by security. I thought fuck this. They couldn't handle my eyes, g - the look of my eyes. That's why I wear shades a lot. Other people get scared by what they see, so I gotta put up a mirror."

His shades aren't on right now but I see why his eyes are better covered when he encounters security. They're dark, brooding and menacingly stoned. He hunches over and points to a paisley rug on the floor; here we go again. "You see that on the floor, g? It's the yin and yang symbol. You go through yin, you end up yang - you go to the yang, you end up yin. I seek light, man - but I know it's in the dark. It's the same shit man, the same shit.

"I'm willing to go deeper and darker. The industry wants to change me, labels want to change me. I can't though - it's just me, my self. My grandfather is the most major influence in my life - I don't want to lose that. He lived with us till I moved out of the house. Everyday, he was ripping me on who I am, where I'm from, where I'm going. He is the main influence for me."

Looking towards future collaborations, Sumach says he plans a reunion with partner-in-crime The Gaslamp Killer, as well as Flying Lotus, who produced his deep, Eastern-infused tune, 'Ancestors'. "We'll meet up again in another space and time," he adds. "But I can't keep recording the same shit, g. It comes from the same place but it feels different 'cos it's about different shit, different experiences, circumstances. It'll be me, flexing it, but light years from what's now." He gives a slow knowing nod, pulls himself up and gathers his fellow beat-makers around while everyone else files out of the room and heads out to the stage, swiping a Red Stripe on the way...

His mad verbiage aside, Sumach's 90-minute set is a banger. Hip-hop heavy with a sub-bass to suffocate your ear drums, he's flanked by his irrepressible tour manager/fellow MC, D.WattsRiot, and backed by San Diego turntablist duo, Skrapez - founded by possibly the nicest DJ in the music industry, Jonathan '10shun' Calzo (part-time librarian, full time beat-maker). The pair's skillful scratching, live electro-tweaking and powerhouse beats are the perfect match for the grizzled Gonjasufi. With a pad out in the desolate Mojave, the desert runs through Sumach's veins but tonight he's a full-fat West Coast MC.

The gig, hosted by the Soundcrash crew, draws on A Sufi and a Killer and his latest dark creation, the mini-album MU.ZZ.LE (before the show, he tells me he actually recorded this back in 2003 - "I just put it out now to fuck with everybody for real. That shit is older than Sufi. It came out afterwards cos it's armageddon in reverse. You gotta reverse them into the pastures sometimes, cos they're very stubborn - you know what I'm saying?" Nope). Amid the constant mix of tunes and DJ wizardry from Skrapez, it wasn't easy to distinguish the tunes as they'd been so radically altered. But memorable moments included The Blame with its soaring anthemic synths, the Arabic psych-drama of Kowboyz and Indians, and the haggard acid-folk of She's Gone, which featured Sumach's most cathartic wails of the whole show, dreads flailing over his baggy white Hendrix T as he stood atop a speaker, baiting the audience. The gig throughout had a good dose of sprawling, free-styled anarchy. Skrapez gave it a more live than premeditated feeling, barely cementing Sumach's raw, haunting vocals with draggy, off-kilter rhythms - in the best possible way. The audience loved it and were kept going well into the night.

The man is pure fear and loathing in the Mojave, no Pacific dream, and has enough southern Californian grit to set him apart from the well-known sounds of LA's Brainfeeder contingency. For a yogi, he's got a seriously full-frontal attitude - very much alive at 4am when he booted some meat-head bouncer from the backstage den, shouting after him, "Yeah bounce, g! BOUNCE!". What can you grasp from Sumach's uniquely baffling chat off-stage and Gonjasufi's rambunctious antics on-stage? If anything, it's that the man does not lack balls - "I'm from the Lord Supreme, g!" he proclaims. "Whatever name you wanna call me, she just tells me, 'You can be whatever you want' - that's gonna be dark man, I'm going in there!". And his music's all the better for it.