The booker at Dalston’s doughty Vortex club introduces the opening night of London Jazz Festival sponsored events defensively; “ It’s business as usual here at the Vortex”. The club crowns the bend in an underground river of London jazz venues, that once surfaced in the back room of the Red Rose in Finsbury park, but now wends from pub cellars in Stoke Newington, down to the self-consciously cutting edge space of Dalston Junction’s Cafe Oto, nurturing jazz’s experimental wing all year long. Tonight this tiny glass attic is packed with discerning twentysomethings and radical pensioners for a trio that seems hand-picked to appease them, representing a venn diagram of distinct but overlapping schools.

Ken Vandermark, on saxophones and clarinet, swifty rose to the top of the Chicago circuit in the ‘90s. With a drill instructor’s moustache and a green and black wardrobe, tonight he plays like a military man on a mission, making bold, definate statements, essaying a kind of volcanic be-bop. The double bassist Barry Guy’s generation of ‘60s British musicians shaped the sound of free improvisation in Europe. He has a painter and decorator’s face, and a ballet dancer’s grace, and plucks an extra fifth string at choice moments, its trebley tone suggesting twinkling stars, before returning to the collapsing sun rumble of beaten bass notes. Mark Sanders, the drummer, currently plays all over the country, all the time, with everyone. Tonight, he drops rubble or sprinkles fairy-dust, as appropriate. In the closing number, Vandermark blows hard and long on the clarinet and ends, literally, on a high note. Outside in Gillet Square one imagines there is a Chinook Helicopter waiting to wisk him away.

On the London Jazz Festival’s second night, a trio led by the German barbarian Peter Brötzmann, another modest coo for the Festival’s experimental fringe, has been invited into the temple of culture that is The Purcell Room. The saxophonist’s 1968 statement Machine Gun laid waste to jazz history and remains a sacred text for American noise rock bands anxious to claim a classy lineage. Brötzmann’s current trio consolidates his position on the front line of possibilities. The electric bassist X Pliakas plays like an escapee from a Norwegian Black Metal band who has run away to join the Free Jazz circus.

The drummer Michael Wertmuller can shift from a sustained, rhythmical assault on the rim of his snare, to a sudden low end battery of the entire kit that makes the audience, as one, gasp like somone had just pushed them off a precipice. Stage right stands Brötzman, sixty eight years old and looking like a Prussian general in sociology lecturer threads, riding the storm. When it subsides, he takes a long and lyrical solo, that appears to appropriate microseconds of Coltrane or Sonny Rollins, showing you what Brötzmann might have done, had he not chosen to make this thrilling and challenging space his own. A standing ovation coaxes the clearly exhausted trio back to the stage. Surely the London Jazz Festival’s other guests can just pack up and go home now? Peter Brötzmann, the big bad wolf of jazz, came to London, and he huffed and he puffed and he blew your house down.