Public Address System
Make your sound louder in public places
This system increases the apparent volume of vocals, musical instruments, other sound sources, or recorded sounds or music. The sound enhancement system can be used in public places where announcers, performers, etc. and need to hear in a remote or large area. Typical applications include sports fields, public transport and facilities, live or recorded music venues and events. A PA system may include multiple microphones or other sources, a mixer to combine and change multiple sources, and multiple amplifiers and speakers for higher volume or wider distribution.
Simple public address systems are commonly used in small rooms such as school rooms, churches and small bars. Acoustic reinforcement systems with many speakers are widely used for presentations in public, institutional and commercial buildings and places such as schools, stadiums, cruise ships and airplanes. Intercom systems installed in many buildings have speakers throughout the building and many rooms have microphones so residents can respond to notifications. Public address and intercom systems are commonly used in emergency communications systems.
What is a Public Address System?
When a large gathering of people is to be addressed, the sound must be amplified so that people away from the stage can listen to it comfortably. This type of system is called as Public Address system or P.A. system.
Requirements of Public Address System
1. It must avoid the acoustic feedback
2. Distribute the sound intensity uniformly.
3. Reduce reverberations.
4. It must use proper speaker orientation.
5. Select proper microphones and loud speaker.
6. It should create a sense of direction.
7. Loud speaker impedances should be matched properly.
8. Proper grounding should be provided. 9. Use closed ring connection for loud speakers.
Factors to be Considered While Selecting A Public Address System
1. The output power of the P.A. system should be adequate for a giving application.
2. Number of microphones that can be connected at the input.
3. Provision to connect a tape recorder or CD player at its input.
4. Provision of a tone control/graphic equalizer circuit.
5. Facility of operating the P.A. system on the DC batteries in the event of power failure.
6. Separate amplitude control for each input microphone.
7. Number of speakers that can be driven by the P.A. system.
8. Facility to use the wireless microphones.
9. Size, weight and cost.
10. Guarantee for reliable operation and after sale service.
PA Systems come in many different shapes and sizes, ranging from the very elaborate systems used in large stadiums all the way down to a simple microphone patched into your home stereo.