Public Address and Background Music
Public address (PA) and background music systems distribute announcements and music across a building by zones. This guide explains microphones and sources, mixer-amplifiers, 100V line speaker distribution, zoning, paging priority and how PA relates to voice evacuation.
Public address (PA) and background music (BGM) systems deliver sound throughout a building — announcements, paging and music — to the right areas at the right volume. From a shopping mall playing music while making paging calls, to an office paging a meeting room, to a transport hub making announcements, these systems are a core part of the low-current package and a key tool for communication and customer experience.
This article explains how a PA/BGM system works: the microphones and music sources that feed it, the mixer-amplifier at its centre, the 100-volt line distribution that drives many loudspeakers efficiently, how the building is divided into zones, how paging takes priority over music, and the important relationship between general PA and dedicated voice-evacuation systems for life safety.
How it works
Inputs come from microphones and music sources. A paging microphone (at a reception desk, security room or call station) lets staff make live announcements, while background music comes from a media player, streaming source or tuner. Each input is a signal that the system must accept, control and route to the chosen areas; a paging station may also include zone-selection buttons so the operator chooses where an announcement goes.
At the heart of the system is a mixer-amplifier (in larger systems, a matrix with separate power amplifiers). It mixes and sets the level of the various inputs, applies any tone shaping, and amplifies the signal to drive the loudspeakers. In a matrix system, it also routes different audio to different zones at the same time — for example, music in a lobby while a page is made only in a car park.
Distribution to the loudspeakers almost always uses a 100-volt line (constant-voltage) system. Instead of matching each speaker directly to the amplifier, the audio is sent at a higher voltage and each loudspeaker has a small transformer with a power tap. This lets many speakers share one amplifier over long cable runs with manageable losses, and makes design simple: the installer just adds up the power tapped by all the speakers and keeps it within the amplifier's rating.
Buildings are divided into zones so sound can be controlled by area. A zone might be a floor, a department, a car park or a public concourse, each able to receive music or paging independently. Zoning lets an operator page only the relevant area, play different background music in different spaces, and control volume per zone — and it is essential for directing announcements where they are needed without disturbing everywhere else.
Priority and life-safety integration are critical. A paging announcement automatically overrides background music in the targeted zones, ducking or muting the music so the message is heard clearly. Most importantly, fire/emergency signals take absolute priority over all other audio. General PA/BGM is distinct from a dedicated voice-alarm/voice-evacuation system, which is a monitored life-safety system used to broadcast emergency evacuation messages; where both exist they must be coordinated, and emergency voice messages always override general PA and music. Voice-evacuation systems fall under fire and life-safety requirements and Civil Defence approval.
Main types
In the UAE
- PA and background music are part of the low-current/ELV scope on UAE retail, commercial, hospitality and transport projects and are coordinated with structured cabling, containment and the electrical supply.
- General PA/BGM must be clearly distinguished from dedicated voice-alarm/voice-evacuation systems, which are life-safety systems subject to fire requirements and Abu Dhabi Civil Defence (ADCD) approval; where both exist, emergency messages take absolute priority.
- Zoning, speaker selection and levels are designed to suit each space and use — from background music in retail to clear paging in car parks — and commissioned and tested at handover.
How GPR applies this
GPR designs and installs public address and background music systems as part of its low-current and ELV scope across Abu Dhabi and the wider UAE. Our teams plan zones, select speakers and 100V line distribution, install paging stations and mixer-amplifiers or matrix systems, and coordinate priority and integration with voice-evacuation and fire systems where required. We deliver clear, well-zoned audio coordinated with the structured cabling and electrical works, from design through installation, testing and handover.
Frequently asked questions
What is a 100V line speaker system?
It is a constant-voltage distribution method where audio is sent at a higher voltage and each speaker has a small transformer with a power tap. This lets many speakers share one amplifier over long cable runs with low losses, and makes design simple by summing the tapped power.
Why are buildings divided into zones?
Zoning lets an operator send paging or music to specific areas independently — paging only a car park, playing different music in a lobby, or setting volume per zone — so announcements reach where they are needed without disturbing everywhere else.
Does paging interrupt background music?
Yes. A paging announcement automatically overrides background music in the targeted zones, ducking or muting the music so the message is heard clearly, then restoring the music afterwards.
Is PA the same as a voice-evacuation system?
No. General PA/BGM is for announcements and music, while a voice-alarm/voice-evacuation system is a monitored life-safety system for emergency evacuation messages, subject to fire requirements and Civil Defence approval. Where both exist, emergency messages take absolute priority.
What speakers are used in car parks and outdoors?
Indoor areas typically use ceiling speakers, while car parks and outdoor areas use horn or weatherproof loudspeakers selected for the harsher environment and the need for clear, intelligible paging over a larger, noisier space.