Diana Ross' storied career has taken her from Motown to Oz. After establishing her soul bona fides with The Supremes, she went solo, taking on gorgeously gospel-tinged R&B tracks like “Reach Out and Touch (Somebody's Hand),” flinty funk throwdowns like “It's My House,” and breathy disco explorations like “Muscles.” And she completely lets loose atop the groovy brass of “Ease On Down the Road #1.”