Sounds from the outskirts of pop

Last fall’s ArthurFest brought more than 40 acts from pop’s experimental frontiers to Barnsdall Park, and now the festival -- the brainchild of counterculture journal Arthur Magazine -- has spawned ArthurBall, which holds forth at the Echo and nearby venues. Likely highlights include the debuts of the Unknown Instructors, which teams ex-Minutemen Mike Watt and George Hurley with Saccharine Trust’s Joe Baiza and Jack Brewer, and the 5:15ers, Queens of the Stone Age leader Josh Homme’s collaboration with Chris Goss. Along with odd folkies, serious noisemakers, psychedelic drones and mutant blues, as well as films, poetry, speakers and art installations.

ArthurBall, the Echo, 1822 Sunset Blvd., L.A., and nearby locations. 4 p.m. Saturday and Sunday. $22 each day, $40 for two days. (213) 413-8200; www.arthurmag.com.