When: Sun., May 10, 7 p.m. 2015
n 1968, the German saxophonist and clarinetist Peter Brötzmann issued Machine Gun, a torrent of riotous free jazz that remains a landmark contribution to the genre. The title befits the era, when protests and radicalism were reshaping European society — particularly in Germany, where the Red Army Faction assassinated its enemies and stayed fashionable — and comparisons to weaponry have followed Brötzmann and his horn ever since. His discography keeps sprouting volumes and his tour-routes are vast. Critically, though, Brötzmann has managed to remain a transgressive, dynamic, and occasionally punishing player in a genre that’s largely predicated on outdoing itself. All of which makes the 74-year-old’s upcoming appearance at The Chapel (777 Valencia St.) — with an ensemble featuring bassist William Parker and drummer Hamid Drake, both esteemed players in their own right — a crucial trip to the firing range.