“There were sheepherders camping in the neighborhood. They had set night watches over their sheep. Suddenly, God’s angel stood among them and God’s glory blazed around them. They were terrified. The angel said, “Don’t be afraid. I’m here to announce a great and joyful event that is meant for everybody, worldwide: A Savior has just been born in David’s town, a Savior who is Messiah and Master. This is what you’re to look for: a baby wrapped in a blanket and lying in a manger.
“At once the angel was joined by a huge angelic choir singing God’s praises:
Glory to God in the heavenly heights,
Peace to all men and women on earth who please him.
“As the angel choir withdrew into heaven, the sheepherders talked it over. “Let’s get over to Bethlehem as fast as we can and see for ourselves what God has revealed to us.” They left, running, and found Mary and Joseph, and the baby lying in the manger. Seeing was believing. They told everyone they met what the angels had said about this child. All who heard the sheepherders were impressed.
“Mary kept all these things to herself, holding them dear, deep within herself. The sheepherders returned and let loose, glorifying and praising God for everything they had heard and seen. It turned out exactly the way they’d been told!”
Luke 2:8-20 The Message
Adventures in Faith & Art 
I don’t think the angels were singing. I know it’s The Message but most translations indicate the angels “said”, Glory to God in the Highest……” Picky, but interesting.