IT WAS EXACTLY 20 YEARS AGO, IN August 1987, that an Icelandic singer with an astonishing voice called Björk first announced herself to the world with a record titled Birthday, the first widely available release by her quixotic indie-pop band The Sugarcubes. It was made single of the week in the rock press and unleashed a torrent of hyperbole that attempted to capture the unearthly appeal of this extraordinary music.
Since then, Bjrk has rarely been out of the news, whether it's leaving The Sugarcubes at the peak of their commercial powers, wearing a swan costume to the Oscars, sewing pearls into her skin for the video to 2001's Pagan Poetry, attacking a television reporter at a Bangkok airport when she tried to talk to her son Sindri, allegedly being so distressed while filming her role for Lars von Trier's Dancer in the Dark that she ate her cardigan, or being the victim, in 1996, of an obsessed fan, Ricardo Lopez, who videoed himself making and mailing an acid bomb to the singer, before committing suicide.
Bjrk, who wowed audiences at Glastonbury 2007 with her theatrical extravaganza of a show and silver-sprayed forehead, may not be as ubiquitous as she was ten years ago, when she was the biggest kooky celebrity on the planet, but her recent album, Volta, confirms her status as the world's most popular out-there musician. These days, she's a sort of avant-garde Madonna, equal parts Diamanda Galas and Destiny's Child, her collaborations with R&B producer Timbaland confirming her commitment to experimental yet accessible music.
"It's quite spontaneous," she says of her current tour, which today finds her in rainy Paris. "I like to exaggerate the atmosphere of a place: sometimes we [Bjrk plus musicians] play the more elegant songs, sometimes the hooligan ones. It varies."
Even though she only landed last night from New York - where she has been filming a video for forthcoming single Wanderlust, and shares a house with her two children and boyfriend, contemporary artist Matthew Barney - Bjrk, 41, looks, not elegant, not hooligan, but effortlessly eccentric.
In a suite at the Sofitel hotel in the city centre, she's wearing a multicoloured Marjan Pejoski dress and leggings daubed with teddy bears and leaves, while her hair falls freely over her shoulders. Relaxing on a couch, she's eating boiled eggs and sipping tea. And doing her level best, as per usual, to avoid being probed about her private life.
Are there aspects of her character that she has never expressed in her music? "That's maybe for somebody else, but not for me, to say. I've been doing this for so long I've definitely had time to separate what's private and what's professional. Then again," she adds, her accent and language as idiosyncratic as her music, "it's kind of abstract because some of my songs are way more private than others, so you wrap them up in silk scarves... I like a performer to be like that: there are certain things I don't want to know; it's unnecessary information. I definitely have cravings for very personal things from performers, but I don't want stuff they don't want to give."
If an alien landed from Mars, which one song of Bjrk's would she play them to best reveal what she's about? "I couldn't pick," comes the curt reply from the veteran interviewee who knows just where this encounter is going.
Would her solo albums, from 1993's Debut to Volta, played back to back, provide a narrative arc of her life? There is a long pause. "No, there are more sides to me than that," she says. A change of subject, then. Has she been pleased with the commercial and critical response to Volta? "Overall, for sure. I'm sort of on my own mission and always felt blessed if other people were into it as well. I've never taken that for granted. But I've never gone out of my way to please anyone; the fact that people are still into it is a bonus."
Is she the world's biggest avant-garde musician? She laughs. "It's a problem that you poor guys [journalists] have, to put everything in boxes. I'm not living in a box.
"I still feel I haven't touched the surface," she says of the ideas she still wants to explore after three decades as a recording artist (she made her first album when she was 11). I'm still trying to get my head around the music I want to make. Hopefully I will have many more years to do that."
Which musician has come closest to sustaining the sort of consistently challenging long-term career that she has in mind? "I don't necessarily look at it like that. Besides, I don't think I've been as extreme as people think I am. I just think change is more natural than staying the same. It's like film directors: just because they make one movie that happens in space, it doesn't mean that their next ten happen in space. Their next one could be a family movie or one set in the 1800s. But a lot of music these days is stagnant. In the last 50 years pop music has become a very profitable thing and the market has made it stagnant.
"To finally answer your question, I have a lot of respect for people like Ravel and Debussy; people who bridged the gap between more serious music and more public music, and were very true to themselves and didn't water themselves down to please anyone."
Is this a conservative time for art and entertainment, particularly rock'n'roll? "It's gone conservative because of the finances controlling it, but at the same time everything's up in the air because of the internet. Everybody's sweatin' and this huge industry, that never owned music anyway, is screaming and shouting."
Does she agree that there's a false sense of anyone-can-do-it democracy today, what with YouTube and MySpace, and that only uniquely gifted individuals like Elvis Presley or Billy Mackenzie or Bjrk herself should ever be allowed near a recording studio?
"Not at all! You're trying to push my buttons. Are you setting me up?" She laughs again. "Anyway, people who really have to make music, like Billy or Elvis, they're going to make music no matter whether they get money for it or not," she continues.
"But also, we're seeing the revenge of the public against the elitist media, and it will find a balance. Eventually there will be room for everyone: people who like reality TV or whatever, and nerds like me doing what we like."
If she'd just started, would Bjrk get signed in 2007 as readily as she was in 1987? "I probably wouldn't even be interested in signing: you can put out your own records on the internet. I would still want to make records, but I wouldn't need the machine."
If she were around 200 years ago, would she have been a musician or, say, an abstract artist? "I would definitely have been into music." Who's the closest person to her in history? "I can't answer that question - it's too kind of like looking at myself from the outside."
Is she the same person as the 11-year-old Bjrk or the 21-year-old who recorded Birthday, or has she shed those skins? "A bit of both. Also, because I'm a singer, from album to album it's always the same voice. If I was an instrumental musician it might be different; I might cling more to my noises. But you're always going to be able to tell I'm a female from Iceland and that English is my second language and maybe guess my age; there's already so much luggage there. Maybe that makes me a bit - not braver, but making it a necessity to change."
Does she have to resist what Nick Cave once described as "being chained to the same bowl of vomit"? Does she have a comfort zone?
She chuckles. "I definitely have my problems, but that's not one of them! I'm a very claustrophobic person, and if there's no surprises it makes me feel like I'm doing a 9 to 5 bank job or something. My attention span or tolerance for repeating myself is probably way lower than Nick Cave's and I probably panic about two years before him. If I was looking at myself from the outside, I'd probably say, 'Look, Bjrk, why don't you do two albums each time?' But I just can't."
In an ideal world, would she make 20-track albums, each song in a different genre? "No, it's more like, I like to spend half the album like Sherlock Holmes, doing detective work, trying to find out, OK, there's this unknown world inside me and I know what it is, and it's like, how do I make that into sounds? There's a lot of time making mistakes and throwing things into the bin, until I find that place. But maybe I enjoy so much the Sherlock Holmes aspect that by the time I've found it I want to find the next thing."
This time, Bjrk chanced upon the twitchy, nervy avant-dance rhythms of Timbaland. What does the appeal of those beats say about us? "Are you trying to say they're Toxic?" she laughs, referencing the Britney Spears single - and no, contrary to current rumours, Britney isn't moving to Iceland to live with Bjrk.
"I think there's a lot of humour in those beats, unlike a lot of today's rock'n'roll. I was so exhausted with rock as a teenager; every aesthetic, even the minimalists like Philip Glass, come from that box, and I was really tired of it. The good thing about that beat thing you're talking about is it establishes a new sort of blueprint. Maybe I was born 20 years too early..."
For the rest of this year, Bjrk is touring one month on, one month off. Between dates, she's contemplating her future and how to stay true to her vision while connecting with the largest number of people - what she calls "the common heart".
"I keep having conversations in my head: should I keep trying to communicate with the common heart, or shouldn't I? Should I retreat, or step forth? I guess while people feel what I do is fresh I'll carry on."
Is this a comfortable level of success for Bjrk now? "I'm very pleased with it," she says. "My daily life has nothing to do with being a celebrity. I do interviews, and I do go on stage, but going on stage I don't feel like a celebrity. When I step on stage I step down to a humble place where I surrender my ego rather than magnify it. And I try to merge with the whole room and become part of it.
"I'm not followed by paparazzi, or very little, and I just hang out with my mates who don't care anyway ... I do the music I want and people still buy my records, so I feel it's a pretty good place. But then again, everything changes. So in a year, everything will be different, and in another year, everything will be different again! So I'd better enjoy it, right?"
• Bjrk plays the Connect Festival, Inveraray, next Sunday 2 September. Volta is out now on One Little Indian.
Bjrk’s quotable quotes
"Football is a fertility festival. Eleven sperm trying to get into the egg. I feel sorry for the goalkeeper."
• "It seems that most the world is driven by the eye, right? They design cities to look great but they always sound horrible, ... They design telephones to look great, but they sound horrible. I think it was about time that the other senses were celebrated."
• "I'm a fountain of blood. In the shape of a girl."
• "The media like drama so it's 'She's in Hell.' And I'm like no, I had a bad day in February and a bad day in September but a brilliant summer."
• "The reason I do interviews is because I'm protecting my songs."
• "When I was a teenager in Iceland people would throw rocks and shout abuse at me because they thought I was weird. I never got that in London no matter what I wore."
• "What probably confuses people is they know a lot about me, but it quite pleases me that there's more they don't know."
• "Matthew [her partner] is obsessed with restraint. The idea that you're stuck between all these gigantic skyscrapers [in Manhattan] is a restraint. And he finds it's a turn-on for him, it excites him. I find that really fascinating, because I'm the other way around. I'm like, put me on the top of a mountain with deer licking my fingers or something, and that's creative to me. That's like heaven."
• "I think everyone's bisexual to some degree or another; it's just a question of whether or not you choose to recognise it and embrace it. Personally, I think choosing between men and women is like choosing between cake and ice-cream. You'd be daft not to try both when there are so many different flavours."
• "I don't like records that are the same from beginning to end, that are too styled and slick. Everything is so designed and airbrushed and Botoxed, it makes us think, 'Oh, everybody's perfect except me. Everything's smooth except me.' But nothing is smooth."