Crystal Castles’ fourth album is the first since frontwoman Alice Glass left in 2014, replaced by Edith Frances. What that means for the band’s chaotic live shows – Glass was agitator-in-chief – is not yet fully clear, but what it means for their records seems not to be a great deal. Glitchy beats, heavily treated vocals and passages of pulverising electronic noise are all still present, and there’s an abiding mood of kohl-eyed gloom. But if the sense of overfamiliarity is a bit disappointing for a band once lauded as experimentalists, producer Ethan Kath has also retained his knack for writing terrific hooks and warped melodies. Ornament and Kept are nuggets of brilliantly disjointed electropop.