Deck the Halls, from Joy to the World. Abridged by User:Adam Cuerden to remove quotes from Simple Gifts and The Twelve Days of Christmas which might confuse the listener - basically, it cuts from just before the end of the second repeat to the conclusion of the piece.
Author: Isaac Watts, performed by United States Air Force Band and Singing Sergeants, recorded November 17-21 Hylton Memorial Chapel, Dale City, Virginia, Conductor Col. Lowell E. Graham arranged by Peter Knight. Modified by Adam Cuerden at en.wikipedia