What Is it About Christmas Music That Gets Us?

Here's a riddle for you: When is a song not exactly a song? When it's a Christmas song.

Sure, holiday hits will take cues from tried-and-true music moves - feel-good chord progressions or dramatic blasts of choral crescendo. But just try to exercise your inner music critic next time you hear that Christmas tune you love to hate or hate to love or just love (chances are, you are not neutral on this subject).

Because there's nothing like the power of music to plumb - and elicit - the depths of human emotion. And there's nothing quite like the holidays to do the same thing, especially since the season comes with a playlist.

Despite the standard radio rotation, the songs that signify the season depend on whom you ask. Head over to Songza, a free music streaming service, and you'll find more than 70 Christmas playlists with spins on the genre that span from reggae and rock to opera, bossa nova and hits cataloged by the decade. There's an album called "Too Yule for Shul: Christmas Schmaltz," featuring classics by Jewish songwriters a la Irving Berlin's "White Christmas," and for the irreverent - a punk rock playlist entitled "Merry F***ing Christmas." Pop artists including Mariah Carey, CeeLo Green, Michael Bublé and Kelly Clarkson have also curated holiday mixes for their fans. These days, 11 of the company's 20 most popular playlists are Christmas-related, says Jessica Suarez, Songza's director of content.

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"There's something really great about hearing things that you grew up with," she says. "If it was not Christmas, I would not be particularly excited to listen to Bing Crosby or to like 'Feliz Navidad'" - the latter tune being one "you can't figure out why people love it so much." For Suarez, it's because her dad loved to sing it. "It reminds me of being home for Christmas," she says.

"Christmas music just seems to make people happier, even when you realize that a lot of Christmas songs are some of the most depressing songs that you hear over the year," she says, referencing George Michael's hit song "Last Christmas." "These songs about longing for someone or missing someone" let people indulge their loneliness, she says. (Case in point: Clarkson's holiday favorites include Dolly Parton's achingly beautiful "Hard Candy Christmas.")

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A Christmas favorite, however, may seriously depart from someone's typical taste in music. Take, for example, a curious musical tradition embraced by Phil Ford, an associate professor of musicology at Indiana University's Jacobs School of Music. As newlyweds, his parents were given a Mario Lanza Christmas album Ford describes as "really over the top and cheesy," replete with a "sobby kind of operatic kind of style of singing," a big-bang backdrop and a "humming chorus of angels." His parents, who liked classical music, played the album for the sake of camp. And it stuck. "It's really easy to start off liking something because it's so bad it's good," he says. And now, he concedes, "I inflict Mario Lanza on my family every year." It's their accompaniment for erecting the tree. "For me, in a sense, what makes great Christmas music is my own experience of it."

And there are those holiday songs he detests - like "Jingle Bell Rock. "I really hate that song," Ford says, sounding a "bum-be-de-ah" mockery of its bouncy beats. "I think it's the fact that I feel like I'm being frogmarched through an emotion [as if] someone's grabbing you by the scruff of the neck and trying to make you feel holiday cheer."

The old carols get it right, according to Ford, noting the examples of "O come, O come, Emmanuel" (particularly the rendition by Joan Baez) and "O Come, All Ye Faithful." "In some way that I can't really put into words, they feel almost indestructible," he says. "You can be bombarded with them every Christmas, and yet, somehow, you always welcome them."

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Indeed, the classics are classics for a reason, explains David Ludwig, dean of artistic programs at the Philadelphia-based Curtis Institute of Music.

"A lot of these songs have existed for hundreds and hundreds of years and have survived the test of time precisely because they're so singable, they're so accessible, they're so flexible," that they can work for a jazz ensemble or group of carolers, he says.

And music, he explains, is fundamental to celebration, be it Christmas or any happy occasion in any culture around the world. "Every celebration we have, I think people feel like it's not quite complete without music," Ludwig says. With Christmas in particular, "music has been really inextricably linked, hand in hand, with the holiday." (Hanukkah tunes, it may be noted, are widely considered lacking - Adam Sandler's "The Hanukkah Song" aside - and Ludwig actually recently composed a cantata to help fill that void.)

Ludwig adds that the winter holidays are a particularly poignant time for music. "When it's most cold out and the bleakest, is sometimes the time when people want to celebrate the most," he says. "[That's when they] want the most warmth and sense of community with each other."

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