Picked this one up thanks to a connection with German free jazz colossus Peter Brötzmann. Zu are an Italian trio consisting of Luca Mai on saxophone, Massimo Pupillo on bass guitar and Jacopo Battaglia on drums; Pupillo plays regularly with Brötzmann in a quartet that goes by the name of Hairy Bones. His ominously throbbing bass is a key element of that group’s sound, which was enough to make me want to check out the most recent release by his core group. Well, even though three-quarters of the Hairy Bones line-up mirrors that of Zu as regards instrumentation (the Brötzmann quartet boasts a trumpeter as well as sax, bass and drums), the two groups could not sound more different. Carboniferous owes little to free jazz, being a heavy and monolithic journey through math rock and metal.