After four months of sprawling, screen-filling epics, the Paramount Summer Classic Film Series flickers to an end on September 2. For those not yet ready for the return of feeling to their posterior nerve endings, never fear! Austin butts shall be kept comfortably numb for at least one more evening. Swans, experimental rock’s most cinematically minded brutalists, have been orchestrating Soundtracks for the Blind for 40 years now. (Add up their collected song lengths and it should come pretty close to 40 years as well.) Latest material, though characteristically grinding, repetitive, and demanding of careful attention, is perhaps their most subdued ever.