Wide-eyed and wild-haired, Devendra Banhart exclaims: "I aspire to feel like a child, how about that!" He doesn't need to say it: moments into our interview it's clear that, in the best possible way, this man is 28 going on 4 years old.
Since 2002, his eclectic, cosmic folk, delivered in Spanish and English with his ethereal vibrato, has allowed both man-child and music to become synonymous with winsome weirdness.
This, after all, is the person who once spent a quarter of an album's recording budget on crystals (as in stones rather than drugs). He's dressed accordingly colourfully, in a Ramones T-shirt with a rainbow coloured scarf over his head - punk rock meets The Magic Roundabout - and after a flurry of exclamations ("Hi! Hey! I love your shoes! I love your dress!") he winds his skinny body on to a chair and starts to fidget. "Is this a sign of nervousness, playing with this rubber band? 'He fumbled like a 4-year-old with his rubber band.' You can certainly say that."
It should be insufferable, but, perhaps because it comes with a fair bit of wildness, his childishness is completely infectious, as evidenced by the countless musicians he's worked with. After his acclaimed 2005 album, Cripple Crow, he was spoken about in the same breath as Joanna Newsom and deemed the linchpin of a movement dubbed "New Weird America". Even 2008's romance with Natalie Portman took on a collaborative bent: you can watch Banhart's then-girlfriend dancing about in Bollywood princess mode for the video of Carmensita.
More recently, and even more bizarrely, he has worked with hip-hop star GZA of the Wu-Tang Clan on a version of his new single Baby.
But his churning imagination and untrammelled playfulness also mean much of what he says isn't exactly true. In his first-ever interview, for example, he thought it would be funny to say that he was done with music.
Today, silly non-truths are interspersed with his reflections on John Cage, Francis Bacon and creativity itself. With metaphors tumbling into one another wildly, his nonsense is almost as interesting as the sense.
As a profoundly un-boring musician, one who is as independent-spirited as they come and the source of almost cultish devotion among his fans, the oddest thing Banhart has done lately is put out his new album, What Will We Be, on Warner Bros.
After years on independent record labels, he can now count Madonna and Cher among his stablemates. So is it strange being a major label artist? "Not yet," he says slowly. "Because majors have changed, it's no different from being on a very, very small indie, one on one. Also," he says, putting on a vaguely British accent, "I would like to perhaps disabuse the perception that we have made our major label album - I'd like to clarify that we made this record not knowing what label it was going to be on."
In other words, he still sounds just as wonderful, if a touch less weird.
His warbling vibrato has been smoothed into a honeyed almost-croon and there's a brimming contentment to the record, particularly with love songs such as Baby and its lyric: "I'm learning to let in all the laughter."
Even without its daydreaming title, What Will We Be is beatific in its sounds and sentiments.
He agrees. "I'm getting older and I'm just coming to terms that I'm stuck with me so I better try to like myself. But also I think that the environment where we recorded had a lot to do with the contentment you hear. We were in this bucolic little northern Californian town in this very small wooden house that was the size of this ... [he gestures to the modest hotel room we're in] ... and half of the stuff was recorded outside. The textural, natural sounds for example - the wind, caressing the grates of the microfilm or ... [here he slips into a German accent] ... "ze crows cawing in ze distance. Suddenly I am [Joseph] Beuys."
There's some riffing as the German conceptual artist before he's back to (relatively) normal: "So there's crows cawing and all these things just happen to happen ... I like to clothe with words the music I feel is appropriate for those words ... and it's been an anthropophagic attitude to what we clothe those words in."
That "anthropophagic attitude" has been helped by an itinerant life. Born in Houston, Texas to hippie parents - a Venezuelan mother and American father - he was brought up in Caracas before returning to the States with his mother and stepfather when he was 14. After dropping out of art school in San Francisco, he moved to Paris aged 18 where, he says: "I was completely homeless. I had a guitar and I had a Discman a friend had given me, but I didn't have a place to live and I didn't have any money."
It was then that folk singer Vashti Bunyan, "saved my life". He wrote to her with some songs and she sent him an encouraging reply. "Through that period of time when I was playing some of the most bottom-of-the-barrel places, it was all OK because Vashti liked it."
Everyone else's opinion seems less important to him. "I keep making music because I haven't made a good record," he says emphatically. "Of course I'm very fortunate in that I think some people like it. A modicum of people like it. My mom, for example. Took her a while but she likes some of my tunes ... my dad, it took him a while but he likes them. But if I felt like nobody liked it I would just move next door to Vashti's house and play for her."
He's just been reading some Prem Rawat (an Indian spiritual leader and 1960s counterculture hero whom his parents followed) and is pretty excited about it. "He said we are equipped with this body, this 'ultimate experience machine'. It's the ultimate experience machine. The chords exist, the words exist, the colours exist, we're just making choices." Could he possibly, like us drearier mortals, ever feel boring?
"Totally," he cries, leaning forward and looking madly intense. "Unquestionably. Deeply boring. Really, I mean I am. I'm deeply conservative and I'm profoundly boring." He smiles and adds: "Dahling."
He insists that he'd rather spend all his time listening to music than playing it or, as he puts it "make a living off being a douchebag", claiming he'd be happy working as a DJ or at a record label ("It's easy to be inspired because there's so much good shit to be inspired by"). He's a visual artist too - the odd and delicate drawings of his albums' cover art are his own - but likewise: "I'd rather curate a show than have a show, y'know what I mean? Everyone's art is so much better than mine.
"You watch someone like Iggy Pop and they're saying, 'Let's get it together, let's attack together.' Or the Butthole Surfers - you think they're attacking you, but really they're doing it together and they're inspiring you to do the same. Just like Joseph Beuys. That was his whole message - everyone's an artist." He goes on, sincerely: "As I get older, there's this new realisation and it's almost like a relief, and that is that I can never be who I once was, but only who I want to become." And who is it he wants to become? He beams. "A nice old lady."
I'm sure he'll be a lovely old lady. Even so, I can't help hoping he doesn't grow too soon.
Who: Devendra Banhart
What: Freaky folky with a collaboration habit - as well as his own solo albums, he's recorded with CocoRosie, Antony Hegarty, Vetiver and many more
Where & when: Essential Stage, 6.35pm-7.25pm
Latest album: What Will We Be