I'm trying to add a pair of outdoor speakers to an existing system and I not familiar with this type of setup. There is a Bogen C10 amplifier hooked up to I believe 6 in-wall ceiling speakers, but only 3 pairs of wires connect to the Bogen amplifier. 3 are connected to the common tap and the other 3 are connected to the 70V tap. How can i incorporate another pair of speakers into this system and do i need a certain type of speakers?
This is a 70 volt PA system.
There will be a transformer by every speaker. These transformers have watt tappings. The number of watts tapped at each speaker must add up the the rated amplifier power, or close. So if you add speakers, you will have to change the taps on the other existing ones. You don't have to have the same power to each speaker. Say you have a 60 watt amp and 10 speakers. You could have 10 watts on four, two watts on two and eight watts on two, for a total of sixty watts. As long as the total watt taps match the amp power, the amplifier will see the correct impedance and deliver its rated power without damage.
The reason for this system is twofold. It allows power to be distributed to speakers according to needs, without loss. It is a high impedance system, so speakers can be hooked up cheaply with bell wire.
This system goes back to the dawn of audio time, is very simple and effective.