Chants can get people into a specific ritual mindset - calming and soothing and centering.
A chant can actually be a set of words repeated tunelessly or it can be set to music. Most of the chants that we use are musical chants. You don't need to have background music in order to use chants in ritual. The mood that you want to set will determine the background, if any, of the chant. If you use any of this material, please site the source.