Katzenjammer is nothing if not distinctive. Formed at an Oslo music schoolin 2005, the four girls play a diverse blend of country, folk, blues, pop and rock. From Tennessee’s Bonnaroo to Australia’s Woodford Folk Festival, the quartet have enraptured tens-of-thousands with their genre-mixing, instrument-swapping and riotous shows. Their 2008 debut, Le Pop, showed that they were as fun on record as live and 2011’s A Kiss Before You Go was a symphonic journey through the emotions, full of vigour and vocal harmonies. Throughout this all they have done things their own way.

Originally consisting of Anne Marit Bergheim, Turid Jørgensen and Marianne Sveen, the trio invited Solveig Heilo to rehearse a few songs with them. Almost instantly, something clicked. Heilo, who played in eight other bands at the time, realised she had to find time to be a part of Katzenjammer. Three then became four. “I think it was just meant to be,” says Anne Marit. The quartet now take another leap with their third full-length, Rockland, an album for which they are – for the first time – the primary songwriters.

Their singular sound is driven by a deep sense of adventure and invention. “It’s about being curious and open to everything. The moment you stop being curious it all stops,” says Anne Marit. This curiosity goes beyond the myriad of styles, extending to the array of unusual musical instruments they use. Take the unofficial “fifth member” – a gigantic, triangular contrabass balalaika they bought on a whim upon seeing it backstage one night. Or the fact that Anne Marit recently moved to a bigger house to have enough space for all of her instruments. The music and instrumentation may vary but what they have created is an aesthetic which is entirely their own.

Rockland is undoubtedly their most refined and accomplished effort so far. “We wanted to go back to the roots and be more stripped and not add all these symphonic things,” says Anne Marit. The moods ebb and flow throughout; from the bass-heavy and rapped ‘Oh My God’ to more serene and melody-led tracks like ‘My Own Tune’ and ‘Lady Grey’. Yet this is no bare-bones record. It is still unmistakably Katzenjammer; a more focused version of the adventure and unbounded excitement for which they are known.

Each member travelled across the world to write songs for Rockland, including separate visits to Nashville for Anne Marit and Marianne and to London for Solveig. A staggering total of 83 songs was the result, though this was reduced to the eleven which make up Rockland. With these they have managed to distil their essence at its purest. “I think it’s kind of even closer to what we want Katzenjammer to be because it’s directly from the source of the band,” says Solveig.

Much like the feeling they had when playing with Solveig for the first time, deciding to work with Australian producer Victor Van Vugt also has an air of fate. Aptly, a cover of Nick Cave and the Bad Seeds’ ‘Henry Lee’ originally produced by none other than Van Vugt himself – was a feature of their early sets. “It’s like the circle is finished,” Solveig says. Unknown to them, Van Vugt was already a fan of their music; having been impressed by a performance on the streets of Austin at SXSW. His diplomatic and meticulous approach to finding the right atmosphere as well as listening to what they wanted to express in the record helped the process hugely.

The group’s ethos is also reflected thematically on Rockland, no more so than on the title track. ‘Rockland’ is Katzenjammer’s musical manifesto. Partly based on Allen Ginsberg’s poem Howl, ‘Rockland’ – the name Ginsberg gave to the psychiatric hospital in which he briefly spent time – deals with the ideas of being an outsider and the concept of individuality.

Solveig explains: “We have our own world in Katzenjammer. We never follow the rules, or try to be commercial when we write music. We’ve always done what we feel like and went with our hearts. It’s not a parallel to getting imprisoned but we’re together in this bubble where the rules are quite different to the rest of the world. That’s what Rockland is a symbol is for.”

Just as this approach underpins their philosophy, their originality and near-unclassifiable brilliance is something that touches people in many ways. Having an impact is one of the main reasons why they make music. Both audience reactions and the feelings that these inspire within are “special” moments which affirm their existence.

“We’re on stage and people are looking for us and getting something that is bigger than them and bigger than us. That’s fantastic,” says Anne Marit. Solveig agrees: “When it comes, you get this moment of realising what you are actually doing. You have to pinch yourself. Most of the time people get really happy. What could be better than that?”