IT ISN’T uncommon for members of long-running rock groups to resent each other.

Bitterness can grow over time, exacerbated by the claustrophobia of touring and strains in the studio. American indie rock band We Are Scientists, however, are a case study in how to maintain harmonious relations.

Keith Murray (singer, guitarist) and Chris Cain (bassist) formed the group in 1999 and remain its only two permanent members. You might think there is even more potential for friction between a touring duo, with all the intimacy that entails, but the reality is very different, says Keith.

“We only still do this because we’re friends and want to hang out with one another,” says the singer. “We meet up in New York when we’re not working on band stuff, which is less common for bands that you might think. People are frequently surprised that I’m often trying to hang out with Chris Cain.”

The dynamic duo crossed over to the mainstream with their breakout 2006 album With Love And Squalor. The fact that the record’s title was taken from an F Scott Fitzgerald short story seemed fitting; it documented tangled relationships and thrilling, chaotic nights in the big city – albeit the band’s native Los Angeles rather than the author’s New York.

Since then We Are Scientists have released four more snappy, immediate pop-rock albums, each of which held a place in the UK charts. Megaplex is their new effort, out on April 27 and produced by Max Hart, who also worked on their last record Helter Seltzer. Hart has also teamed up with a bona fide superstar over the last few years.

“We got Max involved because he had been playing keyboards with Katy Perry on tour,” says Keith. “We were like, ‘if anyone is going to know how to put some pop on our songs, it’s him. He’s a big nerd and wants to think about the technical stuff like waveforms, whereas I want to think about melody.”

Chris has joked that Megaplex was We Are Scientists’ attempt to drop a “fun-bomb” of a record, although their fans will know that the band have always had a knack for light-heartedness and subtle humour.

Keith and Chris had a whopping 90 songs to choose from when it came to devising the tracklist of Megaplex (which has only 10 songs). This surplus was partly due to the “song challenge”, an informal songwriting club run by various alternative musicians in New York.

“It’s an excuse to hang out with friends and drink beer on a weeknight and get away with it by saying you’re working,” says Keith.

“The best thing about it is that instead of thinking, ‘I’m going to write our next hit’, you just enjoy the process. You hear people complain that the fun is taken away when you know that if you write bad songs you might not be able to live in your house anymore. It’s nice to approach songs with utter whimsy.”

The singer adds that he has struggled in the past with self-doubt, constantly asking himself whether his latest creation is good enough for the next planned record. “It’s not super-helpful to think like that,” he says.

We Are Scientists are one of the few remaining indie bands who found success in the mid-2000s. Another are Franz Ferdinand, the Scottish group who Keith references when discussing his band’s relatively long lifespan.

“I loved that first Franz Ferdinand record but if they put out the same album now I probably wouldn’t be into it,” he says. “We tend to ignore the notion that a valuable use of our time is to chase whatever made us popular back then.”

While part of We Are Scientists’ enduring appeal can be put down to the chemistry between Keith and Chris, the duo also know exactly what it takes to survive and evolve in the fast-moving and unforgiving music industry.

“If we stopped being an attractive proposition to listeners,” says Keith, “there would be no reason for us to exist.”

We Are Scientists, Concorde 2, Brighton, May 3, 7.30pm,