Maybe jazz
Actually, I quite like that this is filed under jazz. Extreme metal is closer to free jazz in intensity and experimentation than it is to mainstream rock. When it's good, it locks you in and takes you to the same place, and on a first listen this offering from Nadja is very good, if not quite cutting edge. So, if you've come here for metal and like this album, try some Pharoh Sanders, or, if you normally prefer things a little harder edged, go straight to Peter Brotzmann (Machine Gun, preferably - heaviest piece of recorded music I've ever heard). On the other hand, and if you've stumbled on Nadja while browsing for some free jazz fire music, try Boris (Absolutego for a good long journey) or again, if you prefer things harder, try Blut Aus Nord (MoRT).