The appearance of the second album by Lumen Drones, ‘Umbra’, carries the status of a major event. Coming fully five years after the group’s startling, self-titled debut recording – released, in late 2015, on ECM Records – the long-awaited follow-up marks a significant leap forward. No less experimental than its predecessor, and certainly no less ‘electric’, yet in many ways a deeper and more profound expression of the trio’s interests, ‘Umbra’ is probably some sort of masterpiece.