In this note, we are going to know about the Public Address System for Auditorium which has a large capacity. Welcome to Poly Notes Hub, a leading destination for engineering notes for diploma and degree engineering students.
Author Name: Arun Paul.
Introduction of PA System for Auditorium
A Public Address (PA) System for an auditorium is a type of sound reinforcement system that amplifies and clearly distributes sound to a big group of people. Here’s a description of the necessary components and considerations to consider when installing a PA system for an auditorium:

Key Components of PA System for an Auditorium
Here we have listed some key components of public address system for an auditorium –
- Microphone
- Mixer
- Amplifier
- Speakers
- Digital Signal Processor or DSP
- Cable and Connectors
- Wireless Audio Transmitters
- Backup Power Supply.
Public Address System for Auditorium

An auditorium may be used for a wide range of activities, including public meetings, conferences, and cultural programs. Therefore, the loudspeaker system should have a wide dynamic range (40 dB to 120 dB) and good frequency coverage (from 20 Hz to 16 kHz).
Columns of loudspeakers, with good bass and treble response, should be mounted facing the audience on either side of the stage. If the hall is wide, a small column speaker may also be mounted at the center of the front line.
For effective sound distribution –
- A second pair of small column speakers, slightly inclined, should be placed about one-third of the way down the hall from the front.
- A third pair, also slightly inclined, should be placed at two-thirds of the way down the hall.
- The fourth pair, placed last, does not need to be inclined.
A separate versatile mixer unit is desirable. It may have tape and disc inputs and several microphone inputs. The amplifier should be of 50 to 100 W. There should be a standby amplifier also. Microphones should be of moving-coil type so that they may withstand likely misuse in handling and rock ‘n’ roll music levels. Ribbon types may be used for drama. A typical plan for an auditorium is shown in Fig. If the hall has a line of pillars (not shown in the figure), small loudspeakers may be mounted on the pillars facing the audience (i.e., the back wall). The back wall should be furnished with a good sound-absorbing material.
The height of the side speakers should be such that their axes point towards the ears of the audience, and not towards the floor or ceiling.
Factors to Consider for an Auditorium PA System
Here we have listed some important factors for an auditorium PA System –
- Larger spaces need more powerful speakers and amplifiers
- Higher capacity requires better sound distribution
- Reducing echo and ensuring balanced sound
- Speeches, musical performances, and theater acts require different configurations
- Automated or manual control for sound technicians