Abstract: A sound reproducing system for use with multiple rooms includes a main control unit, and at least one secondary control unit. Thus, the respective automatic level control circuit maintains the voice signal output at a constant level, the respective power amplification circuit of the main control unit converts the voice signal into a larger voice signal, the volume control circuit of the respective secondary control unit converts the larger voice signal and the noise produced during transmission into a smaller voice signal, and the power amplification circuit of the respective secondary control unit converts the smaller voice signal into a larger voice signal output, thereby producing a voice signal output with a higher quality.

Abstract: A power amplification system includes a power supply input interface, a voice source input interface, a plurality of automatic level control circuits, a voice source selection switch, a volume control circuit, a power amplification circuit, an output interface, a microprocessor, an operation device, and an indication device. Thus, the power amplification system has a smaller volume, thereby facilitating storage, packaging and transportation of the power amplification system. In addition, the user only needs to connect the voice sources to the voice source input interface without having to connect external wires, so that the power amplification system is mounted easily and conveniently, thereby facilitating the user mounting the power amplification system. Further, the power amplification system has an inexpensive price, so that the power amplification system satisfies the economic effect.

Abstract: A sound reproducing system for use with multiple rooms includes a main control unit, and at least one secondary control unit. Thus, the respective automatic level control circuit maintains the voice signal output at a constant level, the respective power amplification circuit of the main control unit converts the voice signal into a larger voice signal, the volume control circuit of the respective secondary control unit converts the larger voice signal and the noise produced during transmission into a smaller voice signal, and the power amplification circuit of the respective secondary control unit converts the smaller voice signal into a larger voice signal output, thereby producing a voice signal output with a higher quality.

Abstract: A speaker matcher includes a plurality of selective switches, a first input terminal, a second input terminal, a plurality of power amplifying circuits, a plurality of press switches, a plurality of volume control switches, and a plurality of speaker output terminals. Thus, the different rooms can select different audio sources by switching the selective switches for the different rooms so as to satisfy the requirements of different users. In addition, the different audio sources are output by the speakers for the different rooms.