If you're playing a sung rendition of "Once In Royal David's City" on the radio or even just listening to it on a home system, watch the levels like a hawk. In some versions, the vocals start out relatively faint but crescendo to an almighty volume. (This is especially true in the collaboration between The Chieftains and The Renaissance Singers.) If you're not careful, the loudest passages will sound distorted to listeners. If the levels are set too high on the console, the sudden blasts of sound might blow you back and pin you to a wall.
Needless to say, it's difficult to correct sound levels when you're pinned to a wall.
