To describe The Knife’s new album as ambitious would be to do it a disservice: Shaking The Habitual is so much more than a mere aspirational endeavour; it sounds like a need that had to be fulfilled, a satiated crave.

At the same time, the Swedish duo’s fourth long-player is something of a sonic ordeal. It is hard work and, if at any point you switch off, your attention suddenly re-awakens moments later to a dissonance in your ear that is both unnerving and distressing. You have to concentrate and give this record every part of your attention or you lose any rapport you may have managed to build with it.

Some parallels can be drawn with Kate Bush’s The Dreaming (1982), also the British singer’s fourth release and a similarly difficult departure from her modus operandi to date. The Dreaming led critics to describe Bush in no uncertain terms (“she’s gone mad”) yet it now stands as her most uninhibited collection of songs. It remains to be seen whether Shaking The Habitual will endure as a fan favourite in years to come, but one thing is certain: it’s unlike anything else they’ve ever done before and unlike anything you’re likely to hear again any time soon.

While certain sound remnants from Karin Dreijer Andersson‘s Fever Ray project and the duo’s opera soundtrack, Tomorrow, In A Year may come through here and there in the Swedes’ 2013 incarnation, the sonic palette from which this latest material arises is largely new and previously uncharted. The purely electronic audibles of Silent Shout are replaced by man-made industrial cacophonies and pulses which pitch-shift in a hard-hitting and brave way.

The record’s lead single ‘Full of Fire’ is a long, meandering thunderstorm of beats that sound like they were made on kitchen appliances – dumbfounding on first listen but exhilarating subsequently. When Andersson sings “Questions and the answers can take very long/Here’s a story/What’s your opinion”, she could well be talking about the album in its entirety. You get snippets of The Knife’s story about gender, politics and gender politics and you’re left to form your own view. The process itself may be very long (and this is not just an allusion to the average length of the tracks on Shaking the Habitual but also the time it may take you to digest its offerings) but there is a tacit promise of a reward at the end of it.

Among the (only slightly) more traditionally structured songs on the record, ‘Wrap Your Arms Around Me’ is perhaps the glowing highlight, with its foreboding menace and a skewed, distorted rhythm section of what could easily be slamming metal doors. Andersson’s chants of “wrap your arms around me” waver bleakly against the cold steely sound of the instrumental backdrop.

‘Without You My Life Would Be Boring’ is probably as poppy as Shaking The Habitual can claim to get (not that it would want to). It’s a busy, foot-tapping belly dance flanked by a recorder orchestra and nagging backing vocals. And it’s terrific.

Posing as the interval of a play, ‘Old Dreams Waiting To Be Realized’ – and the near-twenty minutes it takes up in the middle of the album – is testament to the extent of the siblings’ courage with this project. The reality of its inclusion, however, is that it does nothing more than breaking the momentum of the set. It is followed by ‘Raging Lung’, a strong cut which has the essence of exciting hysteria, boasting a fantastic rhythm section and the nearest this album gets to a proper chorus. Sadly, at 9:59 minutes long, it outstays its welcome by more than a third.

Despite its placing towards the back end of the record, ‘Stay Out Here’ serves as a bridge between The Knife circa Silent Shout and the new material. On this occasion, the ten minute sprawl doesn’t feel overbearing but just when one gets a tiny bit comfortable with its digestibility along comes ‘Fracking Fluid Injection’, an equal length cut that serves as a soundtrack to a bad hallucination.

Overall Shaking The Habitual stresses the expansiveness of The Knife’s creativity and it can’t help but punch you right in the gut. It’s an admirable pool of ideas, thrilling noises, rare, unpredictable melodies and a huge amount of imagination but to be brutally frank, it doesn’t encourage repeat listens.