Whether it’s free bands by the river, obscure films at the Silent Movie Theatre or music festivals featuring great non-mainstream bands, Arthur magazine has improved L.A.’s sullied corporate reputation by organizing eclectic, margin-friendly events that embody the magazine’s mission to represent “transgenerational counterculture.” Case in point: Arthur’s Sunday Evenings series at McCabe’s Guitar Shop in Santa Monica, which continues this weekend with eccentric songwriter Michael Hurley and next Sunday evening with psych-rock band Wooden Shjips.......