Portland’s Grails (drummer Emil Amos also plays in Om) returns with Black Tar Prophecies Volume 5, merging the ornate and ambitious sound of their last full-length ‘Deep Politics’ with the murky experimentalism of the previous Black Tar volumes.Black Tar Prophecies has served as a repository for their more idiosyncratic forms of composition where any experimentation that could yield deep-listening rewards was attempted and the results documented in volumes to be compiled later.Black Tar Propheci…