You might think the answer to this question is obvious. A PA system is a system that delivers announcements and messages to the public. But there’s more to a PA system than you would expect. Whether it’s announcing the start of a school day, co-ordinating factory shift changes, or delivering emergency messages, PA systems help keep us informed, organised and safe.
Most, if not all, of us have heard PA systems in action. However, you might not understand how they work, how to choose the right solution for your organisation, or what equipment you need.
Modern PA systems have evolved far beyond simple loudspeakers and microphones. Today, they can integrate with IT networks and support lockdown procedures, amongst other capabilities. As a result, they have become an essential communication tool for schools, factories, offices, sporting venues and many other public and commercial environments.
Conclusion
In this guide, we'll explain what a PA system is and how it has developed over time. We'll also look at where PA systems are commonly used and key factors to consider when choosing a solution for your site. Whether you're planning a new installation or reviewing an existing system, this guide will help you understand the options and make a more informed decision.
What does PA system stand for?
PA system stands for Public Address system.
What is a PA system?
Sometimes called a tannoy, a PA system amplifies sound and clearly distributes it to a wide audience. It is designed for use outside the home, as the name indicates, and can be installed in a wide variety of locations.
To work, a modern PA system needs:
- A microphone – to capture sound
- Mixers – to combine, adjust and control the audio signals
- An amplifier – to boost the audio signal’s strength
- A loudspeaker – to project the amplified sound to its audience
PA systems range from a simple microphone-and-speaker combination used in a small venue, to a hugely powerful and complex kit employed in an arena like Wembley Stadium. They can be portable or permanently installed.
PA systems: The early days
Megaphones were in widespread use before the invention of electric loudspeakers. These cone-shaped devices amplify voices or sounds and project them in a particular direction.
One interesting early example of a PA system use was in America over 100 years ago. In 1910 in Chicago, the Automatic Electric Company, a major telephone switchboard supplier, developed a loudspeaker named the ‘Automatic Enunciator’.
Shortly afterwards, the Automatic Enunciator Company formed to market this new device. Initially, marketing focused on the Enunciator’s use in hotels and its ability to transmit announcements into all public rooms. It was installed at various Chicago locations throughout 1912 and 1913, including the Comiskey Park baseball stadium. The Automatic Enunciator Company marketed its system to hospitals, department stores, factories and railway stations. Sadly, the company was dissolved in 1926. Since then, various companies and inventors – including Marconi – have developed PA and loudspeaker systems.
Where are PA systems commonly used?
PA systems are used in many locations, from leisure centres, transport hubs and hospitals to concert and hospitality venues.
In schools and manufacturing sites, PA systems inform employees and students of the start and end of the working day, of shift changes and break times. Used properly, they ensure transitions between shifts or classes are smooth, improve punctuality and minimise wasted time.
How much does a PA system cost?
As with many products and services, the cost depends on the specification. When choosing your PA system, consider the equipment and features you need, both essential and optional. How much will labour, installation and maintenance cost? Do you need a high level of customisation to meet your facility or site’s needs? Does your budget match your requirements?
How many watts does a PA system need?
A watt, named after 18th century inventor and engineer James Watt, is a unit of power. It measures how fast energy is used or produced. An appliance’s watt rating shows how much power the device draws when it’s operating. In general, a higher wattage will mean higher electrical demand and greater energy use.
Why is this important in a PA system? Because it determines the speakers’ power output and overall system performance.
For a smaller venue, a lower wattage would usually be required, so the sound is clear but not too much. For larger events or venues, a higher wattage will help cut through background noise and reach everyone.
How to choose a PA system
As with the question of wattage, the PA system you choose depends on your site or facility’s size, the audience the system needs to reach, and its intended use. Here are a couple of examples of locations and the factors you need to consider when choosing a PA system.
How to choose a PA system for a factory
- How big is the factory? How many buildings is it comprised of?
- What is the background noise level? Does this vary across the site?
- How will you access the system for installation and maintenance?
- Can the system provide clearly audible sound in all conditions? Also consider how you will communicate with anyone who has hearing impairments
- Can you customise the system to suit your factory’s unique needs?
- Does the supplier provide aftercare, support or a warranty?
How to choose a PA system for a school
- Can the system reach all internal and external areas – classrooms, hallways, dining areas, the gym, playing fields?
- What type of system do you need? IP systems that run over your existing IT network are more flexible and easier to integrate into existing infrastructure
- How does the system complement your lockdown alert plan and help you meet the requirements of Martyn’s Law? Can you customise messages, or set off alerts remotely?
- Is the system versatile, flexible and easy to use?
What a good PA system can do for you
A PA system requires certain pieces of equipment – microphones, speakers, sounders. The quality and price of such kit can vary widely.
Assembling an effective PA system is about more than just practical features like these. Ask yourself – what should a good PA or bell system do for you? It should make your life easier by:
- Improving communication – announcements must be clear, reaching everyone at the same time, to reduce misunderstandings and delays
- Enhancing safety – allowing you to transmit alerts instantly across an entire site in an emergency, or zone them to a particular area
- Boosting efficiency – announcing breaks, start and end of shift times promptly and accurately ensures that you minimise any downtime and maximise productivity or learning time
- Generating consistent messaging – everyone receives the same message at the same time, thereby eliminating confusion that could be caused by passing on a message by word of mouth
- Being future-proof – you can easily expand a modern, IP-based PA system as your organisation grows, because it runs over your IT network. So, there’s no need for disruptive or expensive cabling or building work
The new synchronous clock and bell system has proved highly effective. Every part of the factory is now working to exactly the same time schedule; all shifts and breaks start and end on time, so maximising productivity.
Mark Thomas, Engineering Manager, Ford’s Bridgend Engine Plant, Glamorgan
How PA systems help you boost safety
Martyn’s Law will be fully enforced in 2027, requiring affected premises to take steps to mitigate potential terrorist attacks. In fact, even if your premises are not subject to Martyn’s Law, a good PA system is an invaluable addition to your emergency plans.
You should be able to broadcast a unique lockdown alert, separate from your fire alarm, throughout your premises at the touch of a button. An effective PA system will help improve readiness and confidence, leading to a more effective emergency response.
As part of preparations for Martyn’s Law, check whether your existing system can:
- Issue lockdown instructions quickly and clearly?
- Trigger alerts immediately?
- Reach staff and visitors across multiple areas?
- Deliver messages that are accessible to everyone?
- Help reduce confusion during an emergency?
What not to do: Some common mistakes to avoid
Looking at it from another angle, choosing the right PA system involves more than simply placing an order and having it installed.
A common mistake we often see is organisations choosing a system that isn’t powerful enough for their needs. This leads to poor sound coverage and unclear announcements. This isn’t just unhelpful; in an emergency it could cause dangerous delays if people can’t understand the message. This problem is linked to background noise levels; factories will need different solutions from schools or offices.
Consider where you want to position your speakers. If that isn’t right, then messages will be hard to hear, and your PA system will be less effective. It’s best to look for a solution that can supply indoor and outdoor sounders, to optimise sound transmission.
Will you need to expand the PA system in future, if your site or organisation grows? Make sure that this option is available, so you don’t have to start again or try to bolt a different system onto your existing solution.
How much are you paying for your PA system? The cheapest solution may not be reliable or flexible enough. Equally, spending a lot of money does not guarantee a great result. Consider other factors like system performance and the supplier’s after-care support as well.
How to set up a PA system
If you are having a PA system installed in your factory, school or offices, it will be a fixed installation done by a professional team. Components like speakers can be mounted on walls or installed flush into ceilings for a seamless look and feel.
It’s impossible to cover every possible installation scenario here. However, at Bodet Time, our years of experience in PA and bell systems means that we can meet your needs, whatever they are.
Ensure your organisation communicates effectively
Bodet Time’s bell and PA systems help you improve communication and keep your teams safe. They provide a wide range of wired and remote trigger methods, flexible announcements and visual alert indicators. Synchronised bells help drive improved punctuality and efficiency. Our bell systems can also control other services like heating and lighting, thereby helping to reduce maintenance costs and save time.
We offer you two types of bell system:
- The Melodys range is a wireless system, which means no cabling across equipment.
- Harmonys is an IP solution which runs across your IT network using Power Over Ethernet (POE) to power the system. It enables you to broadcast a dedicated lockdown alert as well as live messages.
Do you need advice on the best PA system for you?
If you’re not sure where to start, call us on 01442 418800 or email enquiries@bodet-time.co.uk. Our friendly team will discuss your requirements and create a bespoke solution.
