The classical crossover duo Due Voci features Kelly Levesque and Tyler Hamilton, a pair of vocalists picked by songwriter Diane Warren to interpret her work with an operatic flourish. Warren teamed with producer Humberto Gatica (who has also worked with Il Volo, Michael Bublé, and Celine Dion) on the project, spending a year-and-a-half auditioning singers before deciding on Levesque, who'd previously worked with Andrea Bocelli and Josh Groban, and was a member of the Three Graces Trio. Hamilton, meanwhile, was a Top Ten finalist on Canadian Idol and performed with Katharine Mc...