Nine rock drummers will perform at once for 45 minutes in the great courtyard at GRIN this Saturday. It’s a re-creation of a 2006 performance by Academy Records (the brainchild of Chicago artist Stephen Lacy), and the show bears the lofty title “Defeat! Thus the Magpie, Rider of Leviathan, Herald of Saturn – The 9 Choirs. (Le Conqueroo III redux).” I have no idea what any of that means but the sound of nine drummers in a brick courtyard should be fun. The show starts at sundown, which is at 6:15 or so these days. Jeez, October.