Three young men from the Swiss Alps in plaid shirts and denim take the stage at Umea's NorrlandsOperan to open 12 Points 2014, and nothing could more clearly signal the current generation's rejection of the conventions of jazz than the instruments they are carrying.

Schnellertollermeier’s weapons of choice are made by Leo Fender and are plugged, through a battery of effects pedals, into loud amplifiers. To open this peripatetic Irish festival, tagged “Europe’s New Jazz”, with such a loud bang is a daring programming decision and there’s nervousness in the air as Schnellertollermeier paste their white noise on to the back wall of the room. It’s part of the beauty of the 12 Points proposition that no one knows what to expect, but if this is jazz, it’s jazz for children from broken homes.

Guitarist Manuel Troller and bassist Andi Schnellmann lean into their task with furrowed brows, stomping on the pedals at their feet while drummer David Meier combines evident technical skill with a flagrant disregard for basic health and safety.

But the good people of Umea are made of sterner stuff - after all, this is the town that gave the world extreme metal demigods Meshuggah; they can take a little ear bleeding around here.

After 15 minutes, the barrage of white noise suddenly stops and there is a generous if somewhat bemused round of applause and even the odd whoop. Troller steps up to the microphone. "That tune was called X ," he says helpfully. "It was our shortest song. We have 10 more to play for you."

It soon turns out that the abstraction of the opener is something like a test of our resolve, and form here on in the band turn to more composed material: angular, tightly arranged riffs passing between bass and guitar, over jagged, odd meter rhythms from the drums.

There are echoes of punk, metal and krautrock, and there is still that sense that it may all descend into chaos at any moment, but beneath Schnellertollermeier’s punkish exterior beats a more urbane heart.

It's no surprise to learn that Troller has studied with the influential Irish-born Swiss-resident guitarist Christy Doran. There are many paths to the waterfall these days, and few members of the younger generation want to call it jazz. But whatever it is, it's the glowing edge of creative music, and in chilly, warmly welcoming Umea, Schnellertollermeier have got it off to a flying start.

Next up is this year's local representative, saxophonist Elin Larsson and her group from Stockholm. This looks much more like jazz with tenor saxophone and trombone out front. And indeed, Larsson is clearly more interested in charming than challenging her audience. Her tunes are full of warmth, mixing jazz influences with Swedish folk and that euphoric, anthemic quality found in contemporary Americana. Not that there isn't an edge here too. The leader is a forceful, passionate player and an accomplished composer with Wayne Shorter on her mind, and in trombonist Kristian Persson she has a second strong voice with which to craft her richly textured arrangements.

The two horns interweave, joining in each other’s solos until it’s not clear (or important) who is taking the lead. Henrik Hallberg’s guitar has an endearing country twang, reminiscent of Bill Frisell, while bassist Niklas Wennström and drummer Johan Käck mix jazz and rock rhythms without prejudice. It’s all heart- warming without being sentimental, with strong melodies that sound familiar the first time you hear them.

There is plenty of talent in the group and the solos develop slowly out of the tunes until it’s not clear what is improvised and what is written. Rapturous applause ensues.

The first night closes in style with Pixel, a quartet from Oslo led by bassist and singer Ellen Wang. It's no mean feat to lay down funky grooves on a double bass and sing at the same time, but Wang makes it look easy and Pixel hit the ground running. If Schnellertollermeier represented one, perhaps masculine brand of new generation genre-bending, then Pixel are coming from the other direction. Landing somewhere between Björk and Beyoncé, Wang's tracks are complex compositions masquerading as throwaway ditties, with lyrics that turn out to be knowing subversions of the usual pap of pop. One of the night's stand-out tracks is the funkily chromatic Call Me - not the usual anguished pleadings of a lovelorn girl but the forceful demands of a woman in control.

The musical depth in Pixel becomes apparent only slowly. With the first few vocal tunes getting the audience softened up, the band turn to more nuanced instrumentals. Trumpeter Jonas Kilmork Vemoy and saxophonist Harald Lassen make two horns sound like more, with echoes of Mingus and Dave Holland, but here also, at last, is the mythical Nordic sound. With Wang and drummer Jon Baar laying down a spacious groove, Vemoy stomps on a reverb pedal and there it is, the sound of the fjords.

But if this is music from a fjord, it’s a pretty funky fjord where Michael Jackson and James Brown are bouncing back off the mountainsides. Venoy and Lassen put down their horns and pick up a cowbell and beer crate for the night’s closer. The two men even add harmony vocals to the chorus that are so good you expect them to start dancing in unison. Maybe that’s next for Pixel.

So this is Europe’s new jazz ? This energising, sociable, genre-defying festival is all about confounding expectations. Day two of 12 Points dawns with the ears well and truly opened. Up here in the far north, where the days last longer, who knows what the night will bring.