Welcome to Christina Aguilera 3.0. Following her previous incarnations of post-Mouseketeer sweetness and the chaps-wearing "Dirrty" era, we have arrived at a kinder, gentler Xtina, both as a judge on "The Voice" and on her stately new single, "We Remain" (Universal Republic).

Aguilera uses her big voice to propel the lovely ballad from the soundtrack to the second "Hunger Games" installment, but she actually uses it sparingly, leaving all her usual vocal adornments behind. The result is elegant and inspiring, and her most potent single since "Beautiful."