On his first solo album in five long years, Berlin techno heavyweight Marcel Dettmann is in scintillating form. The six tracks that make up "Test File" are in some ways typical of his output, in other ways surprisingly atypical. Compare and contrast, for example, the title track's buzzing, mind-altering, percussively dense Berghain techno intensity, and the deliciously low-slung, atmospheric and dubby "Torch", where Dettmann dips the tempo and looks towards post-dubstep rhythms, post-punk and gnarled electronica for inspiration. Or, for that matter, the smooth and atmospheric dub techno hypnotism of "Error (1st Take)", the head-nodding dark-room house haziness of "Autumn 77" and the blistering peak-time techno assault of "Ascending". All hit the mark impressively and bear the hallmarks of Dettmann's signature style, even of their aims are impressively varied.