When singing sensation Jackie Evancho made her television debut on “America’s Got Talent” at the tender age of 10, the judges were stunned by her perfect soprano voice. Soon signed to a record contract, she has since gone on to international fame, selling millions of albums and winning fans among both pop and classical music devotees. The now 15-year-old Evancho comes to Boston’s historic Symphony Hall to promote her third studio album, Awakening. In a bit of a departure, the new collection features not only classical works and re-workings of well-known show tunes, but also more pop-oriented material—including a cover of U2’s “With or Without You”—and some original songs sure to take the young phenom, as well as her fans, to new heights.