pentatonix

Pharrell Williams' song 'Happy' has been danced to all over the world, and now it has been covered by famed a capella group, Pentatonix.

Only seconds into the Pentatonix cover of A Great Big World and Christina Aguilera's hit, 'Say Something,' I was covered in chill bumps. If you are a fan of this beautiful melancholic song, it is a must watch.

Love a cappella music? Then the Sing Off is the singing competition for you, and it returns for a fourth season tonight on NBC. Nick Lachey is back as host along with judges Ben Folds and Shawn Stockman of Boyz II Men, along with new judge Jewel, who replaces Sara Bareilles.