Their debut on Atlantic, 2005's Plans, was written whilst they were riddled with insecurities as to the implications of the move, and named as a nod to the old joke, "how do you make God laugh? You make a plan." Its follow-up is the bleakest and most claustrophobic album in the Death Cab catalogue, appropriately titled Narrow Stairs. Their last record, meanwhile, Codes and Keys, seemed to be about doors opening, literally and figuratively; there were ruminations on the meaning of home and on new beginnings.

The streak remains unbroken with Kintsugi, their first full-length in four years. Literally translating as "golden repair", the title refers to the Japanese art of repairing ceramics by mixing real gold into the resin, meaning that the cracks are now highlighted as an attractive part of the design, rather than hidden as best as possible. It works on plenty of levels. There were always going to be two key talking points with this album; firstly, and most prominently, the departure of founding member and longtime producer Chris Walla, who contributed to Kintsugi start-to-finish before bowing out in order to stop touring and take on production work full-time. The album is also the first since frontman Ben Gibbard, who was happily married - and evidently so - when Codes and Keys was released, divorced Zooey Deschanel and moved from Los Angeles back to Seattle. Both of these splits could have conspired to make Kintsugi an intensely maudlin affair. Instead, in accordance with the meaning behind the title, it finds Gibbard largely at peace with the past.

"We all knew Chris was going to leave the band at some point," says Gibbard on a transatlantic phone call between the competitively rainy cities of Seattle and Manchester. "It wasn't a matter of if. It was a matter of when, and had been for a long time. If there's one thing that being around bands for as long as I have has taught me, it's that what tends to make them work is that the members have similar personalities, and you'll often see that bands have that one guy who's brilliant, but conflicted about his involvement in the band. There's other things he wants to do. For us, Chris was very much that guy."

"We all knew Chris was going to leave the band at some point. It wasn't a matter of if. It was a matter of when"

Gibbard formed Death Cab with Walla when they met as students in the Washington college town of Bellingham in the late nineties, with the former writing the songs and the latter recording them. That was a dynamic that never really changed; once they broke through with Transatlanticism in 2003, the way Walla's nuanced, intelligent work behind the desk complemented Gibbard's viscerally emotive lyrics formed the crux of what made Death Cab one of indie rock's key players. As creatively rich as that relationship was, though, Gibbard hints that it was sometimes a little fraught, too. "There was a sense of relief to knowing Chris was leaving, because it allowed the other three of us to speak much more frankly with him, and have conversations that we might have shied away from in the early days - perhaps because we were worried about setting him off, or saying the wrong thing and having him exit earlier than he ultimately did. It made for a much more open dialogue in the studio, where we didn't have to think about whether we were going to hurt somebody's feelings, or whether they were going to hold a grudge because you didn't like their keyboard part. That's not to pick on Chris, either; we were all capable of behaving that way."

Gibbard and Walla reconvened with bassist Nick Harmer and drummer Jason McGerr in the autumn of 2013, "originally thinking that we'd have a record finished by the end of the year and be back on the road by the next spring." The first indicators of Walla's next move, though, came when he voluntarily stepped aside as producer after some difficult early sessions. "We started making the record with Chris at the helm, but there were a few impasses early on," Gibbard recalls. "He was batting for some aesthetic choices that were very questionable, and it gave us the impression that his heart wasn't in it. There were a couple of times where Jason, Nick and I would go for a walk from the studio, and be like, "are you also not sure about this song? Are you also not really down with where this is going?" It made us pay a little bit more attention to where the album was ultimately headed; normally, we'd just give Chris carte blanche to do whatever he needed to in the studio, because we knew it'd be great. By coming to us and saying that he thought we should go and find somebody else, I think he saved us from a very uncomfortable conversation, where we would have had to suggest it to him. I'm very grateful to Chris that he had the foresight to do that."

It's worth pointing out that Kintsugi was largely recorded a while back now, in the spring of 2014, which perhaps explains why Gibbard's reaction to Walla's decision has, publicly at least, seemed pretty stoic; I was struck by fan footage of the final song the original lineup played together at a festival in Canada last September, which sees him grinning and shouting "see you next time!" as Walla leaves the stage in tears (admittedly, only after an emotional group hug.) "It wasn't like that in the beginning," he explains. "We definitely all went through the five stages of grief. You know, shock, anger and then negotiating - there were some conversations early on that went like, "maybe you can just be on the records, and we'll tour with other people," but we pretty quickly realised that wouldn't work, and that the best thing to do would be to finish the record and call it good. It was Chris' decision, obviously, we weren't making it for him, and the truth is that in the weeks after he told us about it, I was already calling other people to play guitar. I wasn't about to kind of stand in mourning, wondering what we were going to do now. None of us were. We needed to get on with it. He's a friend, it's sad, we miss him, but nobody's died."

Kintsugi was always going to be an important record from Gibbard's perspective even without any change to the band's lineup. Codes and Keys received a decidedly mixed reception both from critics and the group's fans; it was easily their most stylistically ambitious to date, with electronics largely preferred to guitars for the first time, and it also saw Gibbard - living in California at the time - tempering his often downbeat lyrical disposition with some positivity, lending the album an emotional balance that his listeners weren't accustomed to. "I can accept that people don't universally think that it's the best thing we ever made," he laughs. "I'm proud of every record we've done; it's been said by other people, but I do buy into that idea that your albums are like your children - you love them all, but with time, you come to recognise their strengths and weaknesses. Codes and Keys was definitely a departure from a particular type of songwriting that people expect from me, and it very much was not a guitar record, and people expect that from us. I'm a fan of music, and I know that feeling, of not wanting your favourite artists to veer away from what you think they're best at. I still think some of the forays I made into a more minimal style were very effective on that album, but I understand people having an adverse reaction to it, too; it's definitely an outlier, musically and lyrically."

Gibbard was evidently loved-up on that record, and his then-wife's A-list fame lent some of the songs a strange, almost voyeuristic quality; for the first time, Death Cab listeners knew precisely who Gibbard was singing about. At the same time, he was gravitating towards a more forthright, straightforward lyrical style - "I was listening to a lot of Randy Newman, and trying to be economical with my words, less verbose." On Kintsugi, there's at least a partial return to the metaphor and imagery that so defined Gibbard's earlier work, but he still tackles his divorce in startlingly stark terms, especially on "No Room in Frame" and "Black Sun".

"Obviously, there were a lot of things going on in my personal life, and I was initially conflicted about how to present that. I remember talking to Jenny Lewis, who's always one of the first people I run new songs past, and she helped me realise that it'd be going against my instincts as a songwriter to change the way I worked just because I was worried that, rightly or wrongly, people might make assumptions about what it was that I was talking about. To be totally honest, if this album feels like a lyrical throwback in any way, it's because I bought a guitar that forced me to play like I did fifteen years ago. I found myself in possession of an old seventies Fender Mustang that has a small neck; I have stubby fingers, and I always struggled to play guitars with really giant necks. That's what I'd been doing, though, these past few years - playing these Fender G&Ls that were wide-necked, meaning that I wasn't writing parts like I used to. It became a weird chicken-and-egg situation on this record, because playing guitar like I used to seemed to also, at times, drive the lyrics back to a place I hadn't been in a while, too."

There was plenty of time to settle back into the old approach, though; once the band realised they needed to take the unprecedented step of bringing in a producer from outside the Death Cab camp, they made sure not to rush the process. Eventually, they settled on Rich Costey, who came with an impressive two-decade CV that includes work with Muse, Interpol and Foo Fighters. "The concept of having to try to find somebody we could all feel comfortable with was a little daunting," admits Gibbard, "but even as we were changing gears and playing the waiting game until we found the right person, I've got to say I wasn't really overly concerned with the fact that we were going to be away longer than we'd planned. I'm a firm believer in the notion that, when you've been around for as long as we have, you need to go away every so often and let people remember what it is they love about you. I'm not saying that wouldn't have happened if this album had come out in 2014, but based on radio play and how quickly tickets seem to be selling, it seems like people did miss us. We were ready to wait as long as it took to find the right guy. One of the first songs we recorded with Rich was ‘The Ghosts Of Beverly Drive', and I remember listening back to it and realising what a huge improvement it was on both my original demo and the version we cut with Chris. I knew then that we'd made the right call."

Not that there wasn't a little bit of a culture shock; Walla had guided Death Cab through seven LPs before Kintsugi, taking in no shortage of stylsitic variation along the way. In short, the recording process had always been a very insular experience. "There were moments that were trying, for sure, but not because the arrangement was uncomfortable; it was more just the usual stuff, getting stuck with song ideas or whatever. I honestly don't say this as a slight to Chris, but the experience we had with Rich made me wish we'd done it sooner. I came to realise how fucking unorthodox our working arrangement had been for so long. Chris produced all of our records before this one, and he's made the records that will most likely go down as our seminal ones; his brilliance on those records is not in doubt, and I wouldn't change any of them for the world, but working with Rich definitely highlighted how complex a relationship it is when your guitar player is both producing the record and going out on the road to play those songs ad nauseam into the never-ending future."

"One thing that became really obvious was how self-referential we'd become as a band; we were always comparing what we were working on to what we'd done in the past. The song ‘Hold No Guns' on this album is a perfect example; Chris wanted to cut it from the album, because he was viewing it through the eyes of somebody who'd been in this group all these years, and he thought that because we already had an album with a solo acoustic track on it, there was no point in doing it again. Rich wasn't into that; he felt it was a great song, that it provided an important breath on the album, and that he didn't want to allow us to drop songs just because we had another in the same format ten years ago. We'd really needed that, for somebody to come in and cut through all of our bullshit, and tell us straight up what was and wasn't working. That goes for Jason, Nick and myself as much as it did Chris."

In fact, the band were so eager to retain the neutrality of Costey's influence that they decided, when Walla gave his notice early on, that they wouldn't let the producer know until after the final mixes were locked. "He called me, when he eventually found out, and was like, "hey, man, you weren't gonna tell me about this? He didn't seem hurt by it, but he was definitely in need of an explanation. I basically told him that we thought it might adversely affect the working relationship in the studio if the guy in charge knows that somebody else is on his way out as soon as the last chord is struck. After explaining it to him, I think he agreed that it would've had an impact on his read on things - not in a "fuck that guy, he's leaving anyway, so who cares what he says" way, but more in terms of perhaps catering more to the guys he knew would be going out on the road and touring these songs."

Gibbard is now thirty-eight; McGerr and Harmer are both past forty, and both married. Even if Walla hadn't had the motivation of wanting to zero in on his career as a producer, wanting to trade in touring for a more settled home life, as middle age beckoned, might in itself not have been an unreasonable factor in leaving Death Cab behind. Gibbard, though, argues that he himself already has some semblance of that: "even with the solo shows I did and The Postal Service tours, I've still spent less time on the road these past three years than at any point in the last seventeen." He's already made the necessary adjustments to prolong his career as a touring musician; he stopped drinking seven years ago, and speaks effusively of his love for ultra-marathon running, aiming to finish a 100-mile race before he's forty.

"I came to realise how fucking unorthodox our working arrangement had been for so long"

"I spent a large part of my musical career having no other interests outside of music," he explains. "And, you know, I don't have children. I didn't have anything else to distract me until I took up ultra-running. It's provided me with two things: for one, the ability to just switch off, and not think about music for hours and hours at a time. It's important to get away not just from the music itself, but from my identity as a musician, too. When I go to these races and run these long distances, I'm just a runner. Any ego I might have as a musician is completely stripped away. When I'm struggling to finish a really long distance, all I'm doing is suffering in the moment. It grounds me. And then, also, it's really helped me understand that idea of, "it's not a sprint, it's a marathon." If I'm in the middle of making a record and struggling for ideas, or if I'm sick on tour, or in the middle of doing a week of really draining radio interviews or whatever, I've learned to accept the discomfort, continue to put one foot in front of the other, and not quit. It's a very simple idea, but I can't tell you how much of an effect it's had on my life."

The future of Death Cab, beyond that they'll be touring extensively through this year and next with Dave Depper (guitars) and Zac Rae (keyboards) in for Walla, isn't crystal clear, although Gibbard is "pretty confident, at this early stage, that those two will be involved in some way when we come to make another record." What is apparent, though, is that this band has always been Gibbard's lifeblood, and likely always will be, too. "I think there might be a time in my life when I do this less frequently," he concedes. "But as we're ramping up to do this again, I feel like we've gotten better at expressing what we need to take out of these experiences to make them valuable, and worth our time, so to speak. This is what I do for a living, at the end of the day. Unlike Chris, I never had a doubt about where I wanted to be, and what I wanted to be doing; Chris was always torn between being a studio guy and being a musician in a band. I've never had that dilemma. I don't think I ever will."

Kintsugi is available now via Atlantic Records. Death Cab For Cutie play three nights at Shepherd's Bush Empire in June