Although the “20 Zonen” title is derived from the nested structure of this 40-minute work, I will admit that this reviewer—working from a digital promo copy, and not the physical release, which apparently contains liner notes and a color booklet—was not able to discern this shape in the overall work. But that’s not to say “20 Zonen” is anything but a fascinating (though elusive) listen. Right from the opening fanfare, Behrens quickly cuts to other sounds—an airplane, and then, perhaps, some rushing water. Throughout, Behrens combines and contrasts recordings of similar timbre, though their sources often seem disparate. Periodic stretches of silence occur as well, a trick Behrens thankfully does not extend to Lopez-ian durations, while still retaining their ability to surprise the listener, like a long crossfade between Darmstadt and our own physical spaces.
 

“20 Zonen” is particularly lovely in parts, around the 28-minute mark, trickles of what might be water interspersed with transient pops and clicks slowly give way to the slow build of an airplane. Mysterious granular “rainstick” noises (your guess is as good as mine) build amongst the airplane and motor sound while insistent birdcall fills the foreground, with sounds of fire and water clearing the way. Tricky stuff, and definitely worth your time.