Public Address Installation Tips & Advice - 3
So we need another speaker on our system, so how do we wire it?

Simple - extend your wiring from the first speaker and take it to the second, make a connection by wiring in parallel, and take it to the third and so on. The following images show typical through connections at different types of speaker. The advantage of 100v systems are that the connections are simple to make without worrying about series and parallel circuits and impedances.

Horn speaker terminations
The above arrangement is typical of a horn or projection speaker which has a fixed tail cable (grey above), and requires a junction box to make the connection with the fixed wiring which runs from speaker to speaker. Make sure your connections are across the 100v and common and kept in phase throughout.
Ceiling speaker terminations
The above is a typical ceiling speaker connection, one wire from amplifier direction, one wire out to next speaker on the run. When fitted to a ceiling, it is advisable to secure the cables to the speaker chassis or mounting frame with a cable tie to minimise the risk of the cables being pulled out and causing a speaker line fault.

In this image the common wire of the actual speaker is black and the hot is one of the other colours depending upon the wattage setting we wish to use. (Red in this case) Colours will vary according to manufacturer and type of speaker used.
The image below shows the general arrangement in schematic form. The actual speakers are 8 ohm drivers with a transformer connected to enable it to work on the 100v line output.