Forget the model wife, the wild parties and the film star pals, Jamie Cullum tells Declan Cashin why it’s all about the music . . .
I'm a commodity today," says Jamie Cullum, smiling, as he scoffs a banana and a cappuccino in a recording studio in west London early on a Monday morning.
It's the start of a hectic day of contractual promotional duties for his new album – his sixth – Momentum, but he's used to powering on through exhaustion at this point, what with a newborn baby at home (Margot, born in March) and a toddler (Lyra, two) running rings around him and his wife – model and food writer Sophie Dahl.
"It's insane," he laughs. "I haven't quite got to the Red Bull stage yet. But, by this afternoon ... "
He's being facetious, of course, because Cullum is one performer who has never been short (ahem) on energy. His live performances are well-known and cherished for his jig-acting on stage and for his magpie approach to music, introducing covers of pop hits in between the more jazzy, big band, "Sinatra in sneakers" tunes that made him famous to begin with.
Cullum claims, though, to have never watched any clips of himself on YouTube. Nor, for that matter, does he listen to any of his old albums.
"I think some fans have a pretty rough ride with me," he says sheepishly.
"When something new of mine comes out, they're waiting for it and have been living with my last album, and they'll think maybe it will sound like the last one. And, of course, it doesn't. But I think my fans do catch up and, God bless them, they do stick with me."
True to form, Momentum is a different beast that experiments further with styles and sounds, borne of a time that the still-boyish-looking 33-year-old says was "a crossover period" from his wild youth to his more mature thirties.
"You know that time where you're surrounded by friends who are going out all the time, waking up late, feeling terrible and getting back on the horse again. That was very much a life I lived in my twenties," he says.
"Tons of people carry on living that life, but I took a decision to change that. I met someone, and it was so obvious what was going to happen in the next stage of my life, because I wanted to create a life with another person.
"So it felt like when I was writing this album I still had one foot in this teenage crazy life and one foot in this responsible life."
He's on a roll now – the caffeine must have kicked in. "One reason the title 'momentum' makes so much sense is because I think momentum carries you through when you're in your twenties, this kind of optimism that everything is going to turn out okay.
"I think when you hit your thirties or a certain stage of adulthood where you're not just thinking of yourself, you can't really rely on that momentum anymore. You have to make your chances. You don't take your chances."
It's clear from talking to Cullum – and listening to his albums – that he's a creatively restless guy, and while the results of his frequent genre mashes mightn't always be immediately audience-friendly, he's still managed to shift over 10m albums over the last decade, making him one of the UK's most successful musical acts.
Although now he's working while caring for a young family, Cullum isn't one to believe that the "pram in the hall" hampers creativity in any way.
"I don't think it makes a difference – it just means you're more tired," he says.
"In some ways you're in a kind of dream state and you get even better ideas. I have always thought of writing as . . . I don't want to say 'a job' because that makes it sound too boring, but I can't get up and do anything else. I'm a musician and a 'pram in the hall' means you have to manage your time a bit better."
That being said, even a guy as enthusiastic and prolific as Cullum gets stuck sometimes.
"There were days where I'd come in and tell my wife, 'I don't think I can make another record, I don't have any more ideas', and she'd just go, 'No, pick up a tuba and mess round with that'. In that sense, you have to treat it like a job – and the great artists I admire all did that."
His wife – or at least her extended family (her granddad was Roald Dahl) – gets something of a shout-out on Momentum with a cover of Pure Imagination from Willy Wonka and the Chocolate Factory.
Was it meant as a tribute to the in-laws? Or a pre-emptive apology to his missus before hitting the road on tour again?
"I'm really going to have to decide an answer to that question," he laughs. "I'd been messing around with that song long before I met Sophie.
"I love the song, and I thought I could do an interesting version of it. Obviously, I'm connected to that heritage now, and it's one I'm deeply in awe of.
"But my wife has so little to do with that world. She has her own entire career – her only real link is her name. So it kind of feels a bit removed from that.
"But what a thing to be associated with. I'm so proud of her for having stepped into an entire arena of her own where she's highly thought of in her own light. I'm, as ever, in total awe of her."
That's about as much as Cullum has ever said about his and Dahl's lives, as he has assiduously attempted to avoid becoming too much of a celebrity fixture during his decade or so in the spotlight.
"I'll read critics, but I'm good at avoiding the celebrity stuff," he says.
"It's more me coming across stuff I'd read anyway. I think I was in a dentist's waiting room before and I came across a picture of me with a finger in my nose. Or sometimes I'll read something calling me a dwarf."
He laughs at that one – Cullum's height (he's 5ft 4in) has been the source of some media mirth ("jazz hobbit" is bandied about a bit), particularly when he started seeing Dahl, who is six inches taller, in 2007.
"It seems to be okay to call me a dwarf, but I made it worse by marrying a tall woman," he says. "It's like, 'How dare you do that?!'
"But that's literally so far from my experience that it's really something I don't have anything to do with. It's best not to respond to anything. I think it best to just get on with what you do, and shut the fuck up."
My pal Clint
Cullum has been friends for a few years with Hollywood legend Clint Eastwood's musician son Kyle – and it was through this connection that Cullum wrote the title track for Clint's 2008 movie Gran Torino.
Clint, you may recall, has had a bit of bad press in the last year in the wake of a bizarre appearance at last summer's Republican National Convention, when he berated an imaginary Barack Obama in an empty chair on stage.
What's Cullum's take on that?
"Clint apologises to no-one. Nor should he," he replies.
"What I was more interested in was his response. He said, 'Ask an actor to come up and talk and that's what you're going to get'. "You know what? He can do whatever – he doesn't give a fuck!"
Momentum is released on May 20
Day & Night