KT Tunstall’s new album has a split title, Invisible Empire//Crescent Moon.

It is indeed a record of two halves, reflecting a turbulent 12 months that underpinned the creation of the Scottish singer-songwriter’s fourth work.

She has come out the other side with the best reviews of her decade-long solo career and is now playing a short tour this month, ahead of plentiful festival appearances this summer and an autumn series of dates that will include York Barbican on November 12, her only Yorkshire gig that month.

The story begins at the start of 2012, as KT – her full name is Kate Victoria Tunstall – rested after the long touring demands for her third album, Tiger Suit, with no immediate plans for her next project.

However, she then encountered Howe Gelb, of the cult Americana band Giant Sand, and promptly changed tack. Soon she headed to Gelb’s studio in Tucson, Arizona, to write and record songs for what would blossom into the first half of Invisible Empire//Crescent Moon.

She was there for only ten days, but under the influence of her surroundings and new producer, KT found herself in possession of her stripped-back songs of love, death and loss rooted in alt-country, a genre she had long loved but never explored.

The Edinburgh musician returned home, satisfied at the album’s progress. Then her father died, almost mirroring the themes of her recordings. “It was eerie,” she said, singling out the song Carried as being particularly prescient with its story of how the place in which somebody died is not the place where they will be laid to rest, leading to a third party having to make that final journey for them.

“Three months later, I’m carrying my dad’s ashes in a backpack on a train to London,” recalls KT, who soon afterwards split from her drummer husband, Luke, suddenly emboldened to make the break by her father’s death. “So my personal life went crazy; there was a seismic shift in my life...” she said, tailing off.

“By the time I went out for the second recording session in November, I felt like completely different person. Life had changed, and that’s why there’s a real noticeable difference between the two halves of this album. The first half is small sounding and introverted, and then the second half goes widescreen.”

Explaining the transformation, KT says: “When I recorded that half, it had been a few months since all that s*** had happened and I’d started to feel hopeful again. There was a rebirth going on.”

KT, who turned 38 last Sunday, feels her priorities have changed in the past year or so, happiness now replacing work as the most important factor in her life.

“I feel very at ease, all of a sudden. If all goes well with this new album, great; if it goes badly, great too. Either way, I don’t mind what happens,” she said. “I’m really pleased with the album, and I’m getting great feedback, but it’s not the be-all-and-end-all it once was.”

Previously, in a career that has accrued an alleged £8 million fortune from 2005’s Eye To The Telescope, 2007’s Drastic Fantastic and 2010’s Tiger Suit, KT always felt under pressure to achieve more. The relaxed atmosphere of the sessions in the Tucson heat changed all that.

“I had to acclimatise to recording in Tucson,” she said. “Firstly, it’s so hot, you can’t do anything quickly. Secondly, they have their own time over there. In London, everyone is watching the clock, working out how long things are going to take and how much they’re going to get paid.

“In Tucson, we’d say we were starting at 11am, and by 12.30 no-one would be at the studio. I’d say, “Are we starting today or what?”, and Howe would say, “Yeah, but it’s coffee time”.

“It takes a while to adjust, but you can’t fight it. And the funny thing is, you actually get more done – because you’re that much more relaxed, you nail every take when you’re recording.”

KT chose to work with old-fashioned analogue recorders, a more expensive, but quicker method with warmer-sounding results. “I’ve been listening to a lot more vinyl records lately – and this record is coming out on vinyl, which I told the people at my label [Virgin] was very important to me,” she said.

“I love turning a record over when you’ve finished one side. In homage to that, there’s a three-second gap halfway through the CD version of this album, if anyone cares to notice.”

An analogue album with an old-fashioned Side One and Side Two is all part of KT breaking the mould of so many artists in her position, signed to a major label.

“Everyone goes to the hot producer, works in the hot studio, and it all takes so long. It’s no wonder everything sounds the same. Doing things differently is where the good stuff comes from in life,” she said.

“This is definitely the easiest album I’ve ever made; it all felt very natural. And I don’t think it’s a coincidence I had no interference from anyone at the label. I finished it, gave it to them, and now they’re going to sell it, which is how it should be.

“I’ve been so obsessive about work for so long, and I don’t want to be any more. Losing my dad and all the other changes has given me perspective. I feel freer than ever.”