Avant-garde multi-instrumentalist Rhys Chatham is doing a solo tour to promote Pythagorean Dream, his forthcoming album on the British label Foom. Chatham is legendary (in certain very specific circles) for his big guitar orchestra recordings, though his newer stuff isn’t much like that. Heavy on the loops and delay pedals, he’ll be performing on guitar, trumpet, and flutes. Alec K. Redfearn opens.