Quadron are vocalist Coco O and instrumentalist/producer Robin Hannibal, an LA-based Danish neo-soul duo who arrived with a confident self-titled debut in 2010. Avalanche proves a middling followup to that first collection of airy, experimental R&B. Coco's vocals – feted by everyone from Jay Z and Tyler the Creator to Kendrick Lamar (who slips in to guest on the intimate, retro-styled Better Off) – are a joy, blooming with an impressive range across sophisticated, mid-tempo instrumentals that, frustratingly, tend to waft rather than fizz. Avalanche is not without its sweet spots, though; these tend to happen when Quadron turn up the rhythm and let loose, opting for funky, throb'n'glide disco bass on Favourite Star and lively hand-clapped percussion on the big, humming piano-pop of standout single, Hey Love.