The simplest, smallest PA systems consist of a microphone, an amplifier, and one or more loudspeakers. PA systems of this type, often providing 50 to 200 watts of power, often used in small venues such as school auditoriums, churches, and coffeehouse stages. Small PA systems may extend to an entire building, such as a restaurant, store, elementary school or office building. A sound source such as a compact disc player or radio connected to a PA system so that music can played through the system. Smaller, battery-powered 12-volt systems may installed in vehicles such as tour buses or school buses, so that the tour guide and/or driver can speak to all the passengers. Portable systems may be battery powered and/or powered by plugging the system into an electric wall socket. People addressing smaller groups such as information sessions or team meetings may also use for these. Guides who are speaking to clients on walking tours can use Battery-powered systems. Public address systems consist of input sources (microphones, sound playback devices, etc.), amplifiers, control and monitoring equipment (e.g., LED indicator lights, VU meters, headphones), and loudspeakers. Usual input include microphones for speech or singing, direct inputs from musical instruments, and a recorded sound playback device. In non-performance applications, there may be a system that operators or automated equipment uses to select from a number of standard prerecorded messages. These input sources feed into preamplifiers and signal routers that direct the audio signal to selected zones of a facility (e.g., only to one section of a school). The preamplifier signals then pass into the amplifiers. Depending on local practices, these amplifiers usually amplify the audio signals to 50V, 70V, or 100V speaker line level. Control equipment monitors the amplifiers and speaker lines for faults before it reaches the loudspeakers. This control equipment also used to separate zones in a PA system. The loudspeaker converts electrical signals into sound reinforcement system is the combination of microphones, signal processors, amplifiers, and loudspeakers in enclosures all controlled by a mixing console that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience. Public Address System is centralized announcement system installed in Hospital, which enable Code Blue Announce in case of Cardiac Emergency. Public Address System also enable other emergency announcements in case of catastrophic incidents like fire etc. System also used for public announcements on daily basis. Each system consists of a mixing board, sound processing equipment, amplifiers, and speakers. The microphones that used to pick up vocals and amplifier sounds routed through both the main and monitor systems. Audio engineers can set different sound levels for each microphone on the main and monitor systems.
Facilities
Enlisted Below are the main points:
- System Flexibility
- Emergency Announcements
- Easy to Convey Messages Over Large Areas
- Effective Communication