Sound & Public Address

 What is a PA System?

Sound and Public Address is an essential communication tool for any premises or campus. It can broadcast messages to specific zones or throughout the entire facility, ensuring quick and effective communication in emergency situations. Additionally, the system can distribute music or other audio content throughout the building.
In buildings with many people, crowded rooms (hospitals, hotels, penitentiaries, …) are used primarily for the guidance of people in case of fire. Basically, in rooms there are mounted speakers connected to a multi-channel amplifier. The amplifier can have as a signal source: microphone, USB, own memory with preset voice text, etc.. It is also used as a sound system for ambient music, with different areas in buildings.  
In case of fire, it receives a signal from the fire station, automatically stops the music and with a high sound level starts the recorded text to guide the evacuation.
Components of Sound System :

• Audio Mixer
• Microphones  (wired and/or wireless) 
• Speakers
• Power  Amplifiers 
• Outboard Processing Gear
• Cabling
• Monitors
• DI Boxes

1. Audio Mixer:It is an electronic console that processes, manipulates, and combines audio signals before routing them to speakers or anywhere else they need to go. They balance sound, control feedback, and adjust volume levels on microphones.

2.Microphones:Microphones are used to capture sound waves and convert them into electrical signals.

3.Speakers:Like many elements of a PA system, the right speakers you need will be determined by the size of the venue and crowd, and whether it’s being held indoors or outdoors.

4.Power  Amplifiers:A power amplifier increases low-level signals coming from the mixer and broadcast them through speakers. The power level is measured in watts, and you’ll want to be sure you have enough wattage to fill the venue without compromising the quality of your sound. The speakers for corporate events often come with a power amplifier built into them.

5.Outboard Processing Gear:While most mixers have some built-in effects, additional outboard processing equipment can really make a difference. While not necessary at events that will mainly feature speakers, outboard processing equipment can make an impact at musical events by providing the following:

• Compressor: This compresses an audio signal to limit the variation               between loud and soft sounds.
• Limiter: This limits peaks in music to avoid speaker (and eardrum) blowout.
• Reverb: This adds depth and dimension to audio by making it sound as if it’s  reflecting off of surfaces.
• Delay: This creates the sound of a repeating and fading echo.

6.Cabling:Cabling connects all the different parts of the system together so that they can work as one unit.A good quality cabling will last longer and give a better overall quality of sound.
The above components are the main parts common to nearly all PA systems with some variation when it comes to amplifiers and mixers.
If you are using PA for a large venue or live band, you may need some additional components, such as:

7.Monitors: On-stage monitors may be needed so that the band members can hear themselves. As we always place PA speakers in front of the microphone to reduce the risk of feedback, band members cannot hear themselves clearly or even their other band members. On-stage monitors which face the band and not the audience can help with this. 

8.DI Boxes:With all the long cabling needed on stage for a large band, we may need a DI box for guitar signals to boost the signal without adding any external noise into your mixer. 

What should be considered to choose a suitable sound system? 

• Coverage: Ensure that the system can cover the entire area of your facility or campus. Determine whether you need to communicate with specific zones or the entire building.
• Power and Volume: Select a system with the necessary power and volume to broadcast messages in noisy environments.
• Integration: Consider whether the system can be integrated with other communication tools, such as intercoms or two-way radios.
• Durability and Reliability: Choose a system that is built to withstand harsh environments and frequent use.
• Ease of Use: Select a system that is easy to use and requires minimal training to quickly and efficiently communicate important messages to people across your facility.