Public address (PA) systems are employed in large areas to make announcements or otherwise orally communicate with a large group of people in the same general location. Public address systems are frequently used in various public places including subway stations, railway stations, tunnels, airports, and so on. Public address systems allow a speaker to be heard above background noise and/or by a large group of people. In public address systems for use in large venues, such as in large auditoria or outdoors, where high sound levels and/or large audiences are to be covered, it is known to use arrays of loudspeakers mounted above the ground or "overhead" and suspended from above. In the case of such arrays of speakers, the loudspeakers are arranged as one or more columns and are required to be angled relative to each other so as to provide the desired distribution of sound.
