The usually unusual lineups that have graced the annual Spy Music Festival often range from the discordant to the dysplastic. This year’s is no exception: Saturday night’s headliner, Charles Gayle, plays fluid and amorphous jazz sax pieces that can be both free and frightening. Sunday night will feature Aa (or “Big A, Little a,” if you must talk about them), who regularly construct fraught collages of yelps, keyboard beeps, and augmented beats. Joining them over two days are Mystical Weapons (Sean Lennon and Deerhoof’s Greg Saunier), sometime Thurston Moore collaborator Loren Connors, Suzanne Langile, and eight other sonic head-trips.
Sun., Sept. 8, 7 p.m., 2013