The latest from Australian singer-songwriter Angie McMahon is a plaintive ballad that isn’t afraid to dip into the majestic. “Saturn Returning” slowly paces itself with a simple plucked motif that is gradually overtaken by a borderline-bombastic symphonic wall of sound, as McMahon’s voice mirrors itself into a monolithic, over-dubbed chorale. McMahon’s undeniable and versatile skills as a vocalist help elevate …