PA Systems

A Public Address (PA) system is a collection of audio equipment that allows broadcasts over a designated area. Often found in schools and office buildings, PA systems can be used for general announcements or emergency information, providing a simple way to get information out quickly. PA systems can be basic or advanced, and people can customize them to fit a variety of needs. There are even personal models that can be less expensive, but allow for a much shorter range.

General Systems

Basic PA systems are comprised of loudspeakers placed in convenient locations around a broadcasting area, an amplifier to increase the sound, and a mixer that adjusts audio levels. The user speaks into a microphone, and the sound is transmitted through connected cables, or a wireless system, out through the speakers. Some systems also include microphones or intercoms near the speaker locations, allowing the listener to reply to the central location. These responses are not broadcast to the entire system, however, but only to the main user area.

Functions for Schools

Many schools use a PA system to broadcast daily announcements about school activities, and often let students use it to give reports or announce special events. The device can also function as an emergency warning system. In case of fires, earthquakes or other natural disasters, administrators often use a PA system to instruct students and teachers on where to go and how to respond. With the tragic rise in school shootings in the early 21st Century, many schools have installed special emergency warnings through these systems to alert students and staff about a violent attack on the campus.