Cold and gargantuan enough for the Titanic to founder on, Colaris' second album is a testament to post-rock's undiminishing capacity to produce both beauty and brawn. Considering that this is an album made by big bearded Germans with a penchant for naming their songs things like 'Mælstrøm' and 'Harvest', Nexus is an album that soothes far more often than it shreds. Each detuned atmospheric guitar lick slides in over its predecessor like a colony of sea lions in heat. Where other instrumental bands often blow their load early in an effort to maintain the listener's interest without vocals and lyrics, Colaris are content to rescind to foreplay: teasing the listener and pursuing unexpected sonic paths while never failing in their ability to deliver a killer hook when atmosphere and melody will no longer suffice. Similarly the drums are either subdued or absent for much of the albums runtime. However, when the beat truly kicks in (such as on the thunderous 'Cluster') it elevates the surrounding song into the stratosphere.

Last year saw the likes of Pallbearer and Sunn O))) (with a little magic dust from Scott Walker) wrest doom metal into the consciousness of the masses, and the genre's spacious astral aesthetics and guitar wall caverns of sound perfectly complement Colaris' German efficiency and implicit knowledge of when less is more. But the sheer euphoria induced by the likes of the horribly named 'Im Sog' and album highlight 'Shoals' demonstrate a band that are willing to leapfrog a lot of the expected tropes of the scene that spawned them in favour of a brighter vein of progressive rock. The greatest non-vocal bands are able to convey themes and subjects that bypass the language centre of the brain, allowing their unheard words to linger under the surface of a song. Eschewing the subjects of nihilism and mortality that inform a large portion of doom metal (who'd have thought that such an optimistically named genre might contain such pessimistic subject matter?), Nexus' ten tracks are concerned with redemption, forgiveness and the fragility of hope. Or at least I assume. For all I really know the songs could be about getting high and eating pizza while watching old David Hasselhof live videos, and the fact that I was listening to this album when the first pictures of Pluto from New Horizons were published might have coloured my imagination. I doubt it though.

Colaris can't avoid falling foul of some of the typical pitfalls that face any instrumental band. Though their soaring math-metal guitar sound is distinctive, it's also tiresomely unwavering, and the track-to-track sound bleed this causes prevents many of the songs from retaining their own identity. By the time closer 'Harvest (Nexus pt. 2)' comes around, you might be wishing that the band would splash out on a few extra guitar pedals or introduce a string section for the sake of variety. Hell, even a spoken word sample would alleviate the monotony somewhat. But this doesn't take away from the louche perfection of said closer: it's evocative solo echoes the emotive style Anathema have pursued to ever increasing returns and wraps up the album's exhaustive journey nicely.

Ultimately Nexus is a powerful argument for the adage 'limitation breeds perfection'. Colaris have taken a distinctive combination of ingredients and wrung every ounce of potential out of them. The band will definitely have to mix things up in the future (personally I hope they do this by collaborating with the Berlin Philharmonic Orchestra. It would be glorious), but for now the band can rest easy in the knowledge that they've created one of the most beautifully uplifting works of doom metal in recent history.