A basic public address system typically consists of a microphone, an amplifier, a mixer, and loudspeakers.
When these four components are combined sound can be amplified and distributed to multiple zones or areas.
PA systems are used in public, institutional and commercial buildings and locations or places where people congregate.
Public places where PA systems are commonly used are rail terminals, airports, schools, office buildings and places of worship.
PA systems might also be used to convey messages in the case of an emergency.
Before you set out and buy or hire a system it pays to take some time and consider the variables.
Get the power rating right and you're well on your way to successful public broadcasting.
The amount of watts you need really depends on a number of things.
Firstly, what is the size of the venue and what are the acoustic properties of the space? Needless to say, large open spaces require a different approach and most probably increased power.
As bodies absorb sound it helps to know how many people will be in the space.
Large groups absorb large amounts of sound waves so scale up your system if needs be.
Outdoor locations require a great deal more grunt, the sound waves simply dissipate into the sky.
You also need to deal with the fact that you need waterproof speakers for outdoor usage and these speakers typically have a different sound profile.
Many people would describe it as 'tinny' sound, not good for music! Lastly, what are you amplifying? Relatively modest power ratings might suffice for spoken word.
Playing heavy metal instead? Go for large, this type of music benefits from high volume playback.
Once you've established your needs you should spend some time looking up brands, reading manuals and technical data sheets, do research online and speaking to vendors and manufacturers (if you have the opportunity).
The Internet is a great place to start so fire up your computer and get searching! After you have decided on the system that suits your needs best it is important to find an installer with a proven track-record in PA system installation.
There's more to it then installing the devices and wiring them up.
Make sure that a proper sound check has taken place before handover and that you have been adequately instructed in the correct use of the system.
Stick to these tips and your public address system will serve you for many years, if not decades.