It would be a great disservice to pin the usual genre descriptors to the lapels of Sleepytime Gorilla Museum. Part of the Bay Area's avant-garde music family, the ever-churning band offer a fresh blend of cerebral literary references, theatrical flair, and epic sounds that appeal to metal-heads and conservatory students alike. Ominous and exuberant, SGM are best experienced live. Setting the stage tonight are Jason Webley, a soulful one-man band who's as much at home with a squeezebox as he is with a guitar, and Edmund Welles, a bass-clarinet "heavy-chamber" quartet from Oakland.