Introduction to 100v Public Address Systems

Here is a simple system used for announcements in many locations:

This typically comprises of a desk paging microphone, a mixer amplifier and a horn loudspeaker. When the press to talk switch is operated on the microphone, an announcement can be made to the loudspeaker via the amplifier.

In a simple one or two speaker system, standard low impedance speakers can be wired back to an amplifier without too much difficulty, providing the cable distances are not very long.