Anita O’Day’s mastery while singing upbeat, hard-swinging tunes, where her improvisational intuition sparkles, is well-established. But she was also able to navigate slower, more intimate songs and arrangements, savoring melodic shapes with restraint and delicacy. She languidly melts into the lush strings that shimmer beneath the measured rhythm on an insinuating “Angel Eyes,” and there’s a pop polish to a glockenspiel-kissed version of “A Nightingale Sang in Berkeley Square.” Her wonderfully scuffed, lived-in delivery of “I Can’t Get Started” makes all other takes sound glib.