Ray LaMontagne says that there are some days when he doesn’t want to leave his hotel room, such is his aversion to facing the world and the people in it. And when those days come along, the painfully shy singer, whose debut album in 2004, Trouble, notched up half a million sales largely through word of mouth (and, in the process, became an unlikely source of material for the American Idol victors Kelly Clarkson and Taylor Hicks), has no choice but to simply force himself. It’s hard to tell if today is one such day.

At the Opera House in Boston, Massachusetts, his band are already doing a soundcheck when he leaves his room at the nearby Hyatt Hotel to join them. Such is his skill at not drawing attention to himself that you notice his arrival only when he dons his guitar and leans into a mike at the far right of the stage to sing Winter Birds, from his imminent third album, Gossip in the Grain.

The very act of singing – a tender blues rasp of exquisite world-weariness – seems to make him appear. And sure enough, when he stops singing, he is barely there at all. If the song is anything to go by – it’s a hushed paean to nature going about its business, oblivious to human eyes – perhaps the 35-year-old LaMontagne seems that way to the animals too.

Like the female fans who will tell him that they love him between every song he will play later, your instincts towards him are wholly protective. It’s cold backstage. Shouldn’t he be wearing something over his T-shirt? Apparently not. It turns out that, in sharp contrast to, say, Van Halen and their “no brown M&Ms” rule, his rider demands are primarily atmospheric. “I prefer to have it this way. I like to feel cold.” Tempting as it is to trump his social ineptitude with a little of your own – “Cheer up! It might never happen!” – something tells you that the consequences would be catastrophic.

Admittedly, there are moments of levity on Gossip in the Grain. Meg White is a show of support for the White Stripes drummer, who he feels has been maligned by the music press. And, by his standards, the lugubrious ragtime thump of Hey Me, Hey Mama is a veritable hoot. But the truth is that LaMontagne’s popularity presents a paradox that he has yet to untangle. His crippling introversion is what lends his broken-winged folk-soul its power. On the other hand, it’s also why his public performances are so fraught with what the bearded troubadour refers to as “anxieties”.

By his own admission, anxieties pepper LaMontagne’s life. Born in New Hampshire, he was raised with his brother and four sisters by his mother. His childhood was a blur of relocation – a relative’s backyard here, camping on a Tennessee horse ranch there. Perpetually “the new kid” at school, he was victimised. His mother “was very strict. Public [non-commercial] TV was all we were allowed to watch, and in limited doses. There was no candy, no sugary cereals. She was kind of broke, so that maybe helped.”

Of the television he was allowed to watch, the only thing he remembers making any kind of impression were old Doctor Who reruns. “I was a big fan,” he says. Has he seen any of the recent series? How do they compare to the old ones? Finally, reticence gives way to indignation. “There is only one Doctor Who, and that is Tom Baker. He is the only one. That’s it.” Then a pause. “Although William Hartnell was pretty great too.”

I offer to send LaMontagne a DVD of David Tennant as the Doctor – and it’s as though I had offered to sew sardines into the hem of his curtains. “I can’t stand that stuff. The old shows had no special effects, and that’s what made them great. It was so creative. Where is the fun in making everything computer-generated?”

When LaMontagne talks about sitting in the glow of a small black and white TV, watching flickering images of Tom Baker, the memories seem more good than bad. But not to him. “I really don’t think I get nostalgic about anything,” he sighs. How bad does a childhood have to be for memories of it to fail to elicit any nostalgia?

What about records? “We didn’t have a stereo or any of that stuff,” LaMontagne says. “It was literally whatever we could fit into the trunk of the car.”

If LaMontagne really did grow up in a music-free environment, that perhaps accounts for the epiphany that took hold when, woken up by his radio alarm at 4am, he had a life-changing experience. Hearing Treetop Flyer, Stephen Stills’s hymn to leaving the system behind, he left his job in a shoe factory and acknowledged that music may be something that existed in him too.

At 26, eight years after picking up the guitar for the first time, he recorded his voice to see what it sounded like. “I didn’t like it at all,” he says, “although, in truth, it sounded much the same as it does now.”

Perhaps his reticence to do so until this point had something to do with the fact that his estranged father – to whom he has spoken “for about one-and-a-half minutes in the past 20 years” – had also been a musician. LaMontagne says his father knows he ended up making music too but, beyond that, “he’s not worth discussing”.

He talks about his tentative forays into a recording studio as though they were a guilty secret, an extravagance he could ill afford with a wife and two young boys to support. By the time he came to the attention of Ethan Johns – famed for his work with artists such as Ryan Adams, Kings of Leon and Rufus Wainwright, and the producer of Trouble – LaMontagne had trained to become a carpenter.

“He’s come a long way,” says Johns. “He had saved up $5,000 and bought himself some land. While his wife and boys lived in a camper van, he built a log cabin. Then, after they built the cabin, he decided to sell the van and buy a Martin guitar. That was a real iconic moment in his life.”

To call it a happy ending, however, is stretching credulity. “Don’t put your trust in walls/ ’Cause walls will only crush you when they fall,” went Be Here Now, from last year’s album Till The Sun Turns Black. Quite what a follow-up hit to Trouble – and the extra scrutiny it will bring – will do for him is anyone’s guess. But, by releasing the single You are the Best Thing early next year – the sort of radio-friendly R&B rapture that Van Morrison used to trot out in the early Seventies – LaMontagne is sure to find out.

This afternoon, though, he disdains the idea that hit singles have the power to change anything for the worse. “I don’t know what a hit single is. If people like the song, that’s fine. The label makes more money. Maybe that translates to touring, maybe not.”

If LaMontagne talks about being an artist in crude economic terms, it’s probably because his life has been defined by the comforts denied to him until his thirties. He begs to differ, however. The idea that he should give his past adversities credit for his current success horrifies him. “I don’t want to go back,” he reiterates. “I want to keep going forward.”

But aren’t we defined by our past? There’s a sense of entitlement – or a lack of it – to what life has to offer that is forged in childhood. “You feel like you are the same person you were at 14? I always felt 40,” LaMontagne says.

Even in the autumn, when the memory of going back to school fills you with a sense of renewal? That’s surely universal, isn’t it? “I don’t know when kids go back to school,” he says. “I don’t remember when it started. I couldn’t tell you. That is just a different life. A whole other life.”

Gossip in the Grain is released by 14th Floor. Ray LaMontagne tours the UK in February (www.raylamontagne.com)

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