Sigur Ros formed in 1994, taking their name - 'victory rose' - from guitarist Birgisson's little sister. From the outset, they've been creating lush yet barren soundscapes, but their breakthrough didn't come until the release of 1999's Agaetis Byrjun.

They're now on the road promoting Takk, an album containing some of their best work yet. Although they don't stray from their ethereal template, the album plays to their strengths in a layered but seamless way. 'It's been an evolution of sorts, but a natural one,' Birgisson says. 'We never had any idea about what we wanted to do with each album, really. Together, they each reflect the way we have progressed as a band.'

Takk has been a refreshing project for Sigur Ros after the rigours of touring and recording that came with (), their previous album that was released without song titles and sung mainly in 'hopelandic', an improvised phonetic language created by Birgisson. 'We didn't feel that excitement when we recorded (), as we had written the songs a while back and just went in to record them. But with Takk it was so nice to just sit around the studio with our instruments and create the sound from a fresh perspective.'

Sigur Ros' cavernous sound is a group effort by Birgisson, keyboard player Kjartan Sveinsson, bassist Georg Holm and drummer Orri Pall Dyrason, but is shaped mainly by Birgisson, who plays guitar with a cello bow.

A big part of the Sigur Ros experience is their breathtaking light show, which envelops the audience in an opulent, crystallised effect. Some listeners have been known to nod off in their seats, only to be woken by thunderous applause. But Birgisson doesn't have a problem with this. 'It could be pretty nice for people to be sitting there, drifting off and having nice dreams to our music,' he says. 'That's not a bad thing at all, is it?'

Most songs go well over the six-minute mark, often starting off tranquilly and building in epic crescendos. This is yet another Sigur Ros trademark, and one that can prove tiring to the band. 'It'll always depend on your mood,' he says. 'If I'm tired, the heavier songs take a lot of hard work to perform, whereas something like Hey Satan (from Takk) doesn't require as much energy. I'd say on this tour it's my favourite one to play live. But again, if I'm feeling like rocking out, the other songs can be amazing to play.'

Even though the Sigur Ros experience has been hailed as other-worldly and life-changing, they remain fairly unaffected by such praise. 'Sometimes I can't believe people like us so much. I don't read the interviews or music magazines, so I don't put myself in a position where I hear it all the time. But don't get me wrong, it's amazing.

'It's like a crazy bonus when you hear it. We started making music because we love it, and we've stuck with that ethos over the years. We love hearing the positive feedback, but what drives us is our love for music. I'm very lucky to be in this band with great friends.'

You'd think Birgisson would have to pause and think when asked about the highlight of the decade-long adventure, but he shoots back: 'Georg [Holm] recently held a dinner party and it was such a memorable night because no one talked about Sigur Ros for once.'

It's hard to say how the Hong Kong audience will react to the quartet's soaring melodies. The sight of the delicate Birgisson slicing and sweeping at the guitar strings will be something to behold, but the sonic boom the band create has gone down well in Japan.

'Japanese audiences are somewhat reserved,' he says. 'We come onto the stage in the dark, plugging in our instruments. But we feel kind of clumsy, because the whole auditorium is plunged into this deafening silence. Then we start playing and afterwards they clap and cheer, but as soon as they have finished, it's deathly quiet again. It's quite surreal.

'We're so excited about the Hong Kong show. It's going to be our first time there. We were able to add it to the schedule because we had some time between playing Japan and Australia, and it made sense.'

It's natural for Birgisson and the rest of the band to feel the pressures of touring constantly. But would it be so easy to just pack it all in now? He's under no illusions that it will last forever. 'What would I do if I gave it all up? Who knows? Maybe I'd end up working as a gas station attendant.'

Sigur Ros Live in HK, Apr 7, 8pm, HITEC, Kowloon Bay, $480, $590, HK Ticketing, Tom Lee. Inquiries: 2838 8384