Here’s the scene: a fully decorated Christmas tree, a crackling fireplace flickering in the reflection of a champagne glass, red and white stockings and candy canes over the mantel,  a smile from the one you love. Luther Vandross sets the mood with “Please Come Home for Christmas”, followed by Faith Evans jamming to “Santa Baby” and Marvin Gaye with “I Want to Come Home for Christmas”. Slow Jams for Christmas is a joyous, slow-cooking romance-fest that works out very much like an R&B mixtape. It’s quite a treat: 20 songs on a single disc representing five decades of music, from the ‘60s (Nancy Wilson’s “What Are You Doing For New Year’s Eve?”) and ‘70s (“This Christmas” by the Whispers) to 2005 (“Merry Christmas, Darling” by Vanessa Williams). It’s probably the type of album you’d see advertised on a late night infomercial (“Order now, and we’ll throw in this champagne bottle opener!”). But the artists are the draw, with recordings of disparate styles and voices pulled together in a “One Christmas Under a Groove” sort of way. Dianne Reeves absolutely nails “Christmas Time is Here”. Other highlights are Boyz II Men’s ever-popular “Let It Snow”, which plays well year round, as well as Babyface’s medley of “It Came Upon a Midnight/The First Noel”. Toward the middle, the soul vibe dominates, culminating in selections from Al Green, Bobby Womack, Lou Rawls, and Freddie Jackson at the back end. Sweet and marvelous.