Of all the warped offspring spawned from dubstep's umbrella metamorphosis, Scottish-born producer Steve ‘Kode9’ Goodman and cerebral pal Stephen ‘The Spaceape’ Gordon stand tall at the very scalpel-sharp edge of its boundary-slashing evolution. And with second album Black Sun – arriving a full five years since standard-setting debut Memories of the Future – they effortlessly breach the stratosphere once more.

Hyperdub label figurehead Goodman's sparse and eerily inhuman beats, both spatial and spacey, invade the outer reaches of your hearing with silent coup virulence. But Black Sun also has the gears to switch up from slow-building subtlety. Where a pair of initial brain feeders – Black Smoke and Promises – contain much spiritual fulfilment, Am I subsequently drops with the propulsion of Rhythm and Stealth-era Leftfield had they been kidnapped by Lee "Scratch" Perry during one of his more lucid periods.

Having been instrumental in the manner the duo have emphasised the 'dub' into dubstep, then swiftly transcended the genre entirely, Gordon's deep, conscious vocal wisdom continues a commitment to reimagining dub's Rastafarian soul as an alien musical force. He has sweet-larynxed back-up here too, though, from Shanghai-based singer Cha Cha, who grasps the baton for three consecutive tracks that pull at the senses. At junctures such as Love is the Drug, the results wield similar effects to fellow Hyperdub project King Midas Sound, an almost academic antithesis to basic base-level bass that has consumed many compatriots.

As Black Sun's evocative mantle screams, the record hums with a menacing darkness. Yet it's not paranoid urban dread, more an unknown extraterrestrial force stalking your moods. Bullet Against Bone, for one, is a perfect illustration of the bassbin ghosts marching through the record. After blasting beyond gravity and mortal atmospheres, it's fitting that Black Sun should launch its final descent to Earth with closing collaboration and live set staple Kryon, featuring solar system-cracking kindred spirit Flying Lotus, switching on the atmospheric synth afterburners to lush effect. When a lunar time capsule next needs a musical artefact of almost indeterminable age, Kode9 & The Spaceape are your men.