Nothing quite encapsulates the year in music like a solid radio holiday concert. The popular Christmastime tradition is in full swing in Boston this week, with Mix 104.1’s holiday festivities sandwiched in the middle. The station’s “Not So Silent Night” enlisted electric violinist Lindsey Stirling, critically acclaimed alt-rock crooner James Bay and pop diva Meghan Trainor to tantalize fans last Tuesday, Dec. 6. When Trainor was forced to cancel her set just five hours before showtime, “Fight Song” songstress Rachel Platten filled in with plenty of spark and optimism. Together, the three artists amped up the crowd of Mix 104.1 contest winners and energized them for the quickly approaching holiday season. Flip through the Buzz’s gallery from the evening.