It’s some four years since the release of Bison’s acclaimed debut single, "Way To L.A", the result of a series of productive studio sessions between Paul "Mudd" Murphy, longtime collaborator Ben Smith, krautrock legend Holgar Czukay and vocalist Ursula Major. Since then, Murphy and Smith have made a number of return trips to CAN's Innerspace Studio in Cologne, where Czukay famously conjures his out-there musical magic. The result is Travellers, the quartet's long-promised debut album. It is, by anyone's standards, a deliciously dubby and intergalactic concoction; a fearlessly atmospheric blend of krautrock and dub disco-inspired grooves, delay-laden horns, quirky percussion, stargazing electronics and eyes-wide-shut vocals. The dub influence is particularly notable given Bison's love of "versioning" tracks. Three of the tracks – "Way To L.A", "New Moon Boy", and "Familiar Stranger" (the latter two mixed by Conrad Idjut, who also turns the album's title track into a clandestine, French-horn-laden late night masterpiece) – appear in "Day" and "Night" versions. Meanwhile, previous single "Mandy" – a murky spaced-out stroll though the collective Bison hivemind – is also included in two forms, with the Balearic stoner rock of the "Power Boy Mix" offering a sun-kissed (but still deliciously atmospheric) reinterpretation. Highlights are naturally plentiful, with Ursula Major's half-spoken, half-whispered vocals wrapping themselves around spacious rhythms, shuffling drums, twinkling, effects-laden guitars and low-slung basslines. Travellers is an album rich on otherworldly intent, sparse grooves and thick, enveloping production. It's exactly the sort of album you'd expect from musicians and producers of this calibre. We may have been waiting a while, but Bison have definitely delivered.