They grow up so fast. It's almost two years since yours truly first met Lar Kaye and Conor Adams as All Tvvins, a group with no more than a handful of headline shows to their name. They'd scarcely released proper material, either; guerrilla-style studio videos outnumbered actual recorded tracks. Their festival slots would, in the wrestling industry, have been termed 'curtain-raisers', as they typically kicked off as the gates opened. And, perhaps most notably, their enthusiasm for their new project oozed from every pore - "We're like kids at Christmas" could have made it onto merchandise as the official band catchphrase.

They're now grizzled road warriors, who've seen more of Europe than Napoleon did. Following a string of impressive singles, their debut album IIVV is primed to storm the charts, rubberstamping their arrival as a bonafide force in Irish music. Accordingly, their rise up the bill at summer weekenders has been inexorable, and they're now firmly installed as festival favourites. But one thing, thankfully, hasn't changed much.

"You have to be excited," Conor says. "It has to be fun. Otherwise you're going to dread it, and you just wouldn't do it!" "The majority of the time, that excitement doesn't go away," Lar interjects. "But you do have to accept that if you're working on music full-time, you're not always going to have that Christmas morning feeling."

Be that as it may, the run-up to the release of their first LP probably felt much like waiting for Santa to pull the finger out and put in his annual shift. If it had been their choice entirely, the duo admit, the record would have been out long ago. But with the benefit of hindsight, they accept that the slow-and-steady approach has paid handsome dividends. "We had the luxury of time, and a label that didn't want to force us into a release date," Lar explains. "If we didn't have that luxury, then it would have been a very different album."

Time, however, can be a blessing and a curse - and Lar doesn't need telling. "I had sessions that I did myself that were crazy," he laughs. "I'm guilty of overcomplicating things - that's just in my nature. And they're things that, when you play them for Conor, he'll tell you that they're madness. But he's also great at focusing on the one thing - that single element of the mess - that might be a good starting point for something else. The loop for 'Thank You', for instance, came from one of those."

That track may well be the pick of the 10 tracks on IIVV - but it's far from a mission statement. In fact, there's no one cut that would neatly sum up their sound, which strides confidently from spiky post-punk to funky new wave; from the shimmering art-pop of 'These 4 Words' to the '80s synth-soaked 'Darkest Ocean'. The variety will be of little surprise to anyone familiar with their past lives - Lar as guitarist of experimental instrumentalists Adebisi Shank, Conor the frontman of alt. rockers The Cast Of Cheers. But it was when they agreed not to meet in the middle that a world of possibilities opened up. "Conor and I had to understand for ourselves what this band sounds like," Lar admits. "To be honest, I think we're still figuring it out. But that's a good thing not to know. If there was a certain pathway, or a certain process to making an All Tvvins song, then that would take away the mystery of getting there."

Conor picks up the thought, as happens a lot with these two - attached at the hip for the past few years, finishing their own sentences has become an unnecessary chore. "The main role of the producers on this album was to peel things back. There were mad suggestions thrown about, pulling us in directions we wouldn't normally have gone. At one point, I recorded the poppiest vocal you've ever heard - a chart pop vocal, a getting-sick-on-yourself vocal - and it wasn't good. But there was something in it, halfway through, where you think 'That phrase works', and you go from there."

And while the producers involved can boast an impressive body of work - Arcade Fire, Adele and Kasabian just a handful of the names involved - their credits are dwarfed by the mammoth list of comparisons which have been flung in the direction of All Tvvins. Foals and Bloc Party have been mentioned. The Police and Talking Heads, likewise. Two Door Cinema Club; Bombay Bicycle Club; Editors; do stop us if it's getting irritating, boys. "People always want to relate it to something," Lar reasons. "There's not many reviews that say 'well, this has never been done before'. But, y'know, how do you do something new? Your dad's music in the car, your older brother's record collection, the theme from MacGyver, 2 Unlimited; the shit when you're a kid and you have no filter, it's all an influence. The references used to piss me off, but then I realised they made perfect sense - because I listened to the things they mentioned."

It's not everyday that rock bands are saluting the MacGyvers and 2 Unlimiteds of the world, but maturity has now allowed them to embrace that filthiest of three-letter words. "When you're a teenager, and you like Smashing Pumpkins, then that's your route. I had an aversion to pop music; even Coldplay was like 'ugh, mellow rock'. Now that I have ten more years on me, I listen back and see they had some pretty amazing tunes. I was an idiot. I should have listened to them - to everything, in fact." "You run away from it when you're growing up," Lar says. "But pop is such a wide genre. Even Justin Bieber's singles last year had these really cool snare sounds and weird minimal drops - stuff you really don't hear a lot. I mean, it's just 'popular music' - and I'm pretty happy playing 'popular music.'"

Indeed, the duo's popularity extends way beyond our humble isle; tastemakers and punters across the Irish Sea and elsewhere have happily leapt onto the bandwagon, which is why Lar confirms the UK is a massive focus in the upcoming months. "Things might be going well in Ireland, but there's only so many rounds of the country you can do. But you have to know there's a crazy amount of work involved to make an impact. A bigger place, with bigger bands, takes more work."

"And there's no magic trick," Conor points out. "We talk to other bands, and they tell us 'gig, tour, tour, gig'. That's the only answer." Just as well the enthusiasm remains.