A method of using transformers at the output of an amplifier and at the input of the speakers. This allows multiple speakers to be connected to a single amplifier. Care must still be taken to insure the load (speakers) do not overload the amplifier's output. This method is commonly used for paging systems or systems where many small speakers are used. The biggest loss when using a constant voltage system (also called a distributed system) is that of frequency. Unless very high quality (expensive) transformers are used, low frequencies are lost.
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