With most musicians who have quit an established band to strike out as a solo artist, getting them to talk about the group they’ve left is well nigh impossible. With Charlotte Hatherley, until last year the guitarist in the chart-topping Belfast indie-rockers Ash, keeping her off the subject is the challenge. Clearly still in shock, 14 months on, about the manner of her departure, the 27-year-old rows back discussion of her new album, The Deep Blue, to the circumstances it sprang from. And those circumstances sound, for all the blandishments used to announce her exit, rather brutal. “After nine years, Ash and Charlotte Hatherley have mutually agreed to part company. The decision is completely amicable and they wish each other the very best for the future,” the statement ran. Seems straightforward. In reality, Hatherley had agreed to meet her bandmates over lunch in New York to discuss plans, after the completion of a mammoth tour to promote their fourth album, Meltdown.

Crucially, the conversation also took place in the context of Hatherley’s own solo debut, 2004’s Grey Will Fade, and the alteration in the group dynamic that record’s critical thumbs-up had effected. “It wasn’t really my choice,” she reflects on the decision. “It was me sitting down with them and them saying, ‘Maybe you should leave.’ And they said, ‘We’re going to release it to the press this evening.’ I didn’t have time to prepare.” That’s not entirely true, though. By her own admission, Hatherley had been giving mixed signals for a long time. “It’s something I’d wanted for about a year,” she says, “because my heart wasn’t really in it. And I think they knew that I would have preferred to do what I wanted to do.” If her departure remains a thorny issue, then Hatherley’s entry into Ash was controversial, too. Having bunked off school and joined a band at 15, in the chaotic wake of her parents’ divorce, the Londoner was head-hunted by Ash’s front man, Tim Wheeler, when she was just 18. The band’s predominantly female fan base wailed, but her arrival brought in a new, male audience — and, with it, the beginnings of a fantasy construct around the new guitarist as a femme fatale , thrashing at her instrument, and more than likely (they hoped) to rip their hearts out and stamp them underfoot. Hatherley’s expression, when reminded of this pin-up status, suggests otherwise.

“In that male-orientated environment,” she says, “you’re either going to isolate yourself even further by being a real girl, or you’re going to become one of the boys. And I really embraced the latter lifestyle. But that perception couldn’t be further from the truth. I usually find that people expect me to be really icy and hard. The number of times I’ve met people and they’ve said afterwards, ‘Oh, I thought I was going to be really scared of you, but actually you’re really nice.’ Or, ‘You don’t really smile very much on stage, do you?’ And I was like, ‘Well, nobody else does.’”

This misconception was a factor in the trouble Hatherley had securing a record deal once she’d left Ash. On the face of it, the equation seems simple. The former guitarist in a multi-platinum band, one superb album of spiky bubble-gum rock under her belt, another belter ready-wrapped for release, a face to launch a thousand male bedsit fantasies: you’d sign her on the spot, right? Wrong.

“After being in a successful band for almost 10 years,” says Hatherley, “taking my album and sitting in a label office and being told it wasn’t good enough, that it needed to be rerecorded, or reproduced, was quite difficult. I found it a really disheartening process. But they want an instant thing, and have quite unrealistic expectations about what should be achieved.”

Hatherley made The Deep Blue with the team that contributed to Grey Will Fade — the Captain Beefheart collaborator Eric Drew Feldman and PJ Harvey’s longtime drummer and percussionist, Rob Ellis. The recording sessions, in an idyllic studio on the coast of Le Marche, in Italy, for three months last summer, helped her overcome her panic over the Ash fallout. “It was just us three on mopeds,” Hatherley recalls. “We’d take the weekends off and go to the sea. There was no competition. It was very different.”

The 12 tracks deepen the sonic palette and lyrical subject matter of Grey Will Fade, harking back to that album’s bracingly unpredictable chord structures and Breeders-meet-Ramones melodies, but taking more of a breather than Hatherley’s early songs did. She co-wrote one track, Dawn Treader, with XTC’s Andy Partridge in his garden shed. “I was actually sitting there with one of my heroes, and he’s screaming these lyrics at me. He’s been a bit of a big brother actually, similar to Captain Beefheart with PJ Harvey. Just phone calls, you know: ‘Give me a call whenever you like.’ And because he’s a bit of a recluse, he’s a big chatterer.”

At the time of Grey Will Fade, Hatherley tended to hide her solo light under a bushel, a process that became harder as the favourable reviews rolled in. “As reliable as Tim Wheeler usually is,” ran one, “it might not be a bad idea for Ash to install a fail-safe just in case their front man’s well of pop sensibility runs temporarily dry, and on the evidence of Grey Will Fade, Charlotte Hatherley might just be what they’re looking for.” That must have gone down like a lead balloon. “And I’d really played it down,” Hatherley laughs, “I was like, ‘Oh, it’s just a stupid little thing, don’t worry about it.’”

If they didn’t worry about it, it’s possible nonetheless that Ash picked up on an ambivalence in Hatherley that she admits she still sometimes struggles with. “There is part of me,” she says, “that is really reluctant to embrace the solo thing.” In part, she says, this is the natural insecurity of someone who was cushioned from struggle by a huge touring and management operation for so long. But it’s also the result of finally grappling with long-avoided emotions: about coming from a broken home; about her feelings of inadequacy and fraudulence in becoming a member of a stadium band overnight; about the sense of identity she felt she lost along the way. “I wanted to get away from that thing with Grey Will Fade — the poppy-punky, ‘Oh, it’s a nice record for a side project’ thing. I’m going to be 28 this year, and I want to feel that age, instead of constantly being the 18-year-old who joined Ash. It’s taken me 10 years to be able to write a song about my parents; it’s the first time I’ve been in a studio and sung a song that’s made me want to cry. With The Deep Blue, it was a case of, ‘This makes me really embarrassed and nervous. So it’s going to stay.’ I realised it was okay to be honest, because I have a tendency to make sure everything seems fine. When, clearly, everything was not fine.”

Last week, on the day her album was released, she played her new songs to a packed crowd in Oxford — and her on-stage demeanour spoke volumes. Okay, she still doesn’t smile, but her eyes, the urgency of her singing, the lack of that old reluctance, all said one thing: “This is me. There’s no ‘maybe’ about it.”

The Deep Blue is out now on Little Sister

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