It’s all about those honeyed harmonies on this winning collection of festive favorites from a classic vocal group. Drawing on doo-wop, soul, and blues, The Platters’ voices melt into each other over sighing strings on dreamy versions of “White Christmas,” “Silent Night,” and “Auld Lang Syne.” Their massed singing sounds weightless and angelic, seamlessly meshing even when they ratchet up the tempo and start swinging on “Santa Claus Is Comin’ to Town” and “Jingle Bell Rock.”