The network public address system intelligentization requires timing sound source, power supply, partition, and firefighting radio linkage, so it has equipment such as a timer, program timing player, power sequencer, audio matrix, central control host, fire-fighting collector, etc.
Although it is simple, the requirements vary with different systems and transmission ways, it is generally divided into four kinds, they are an analog audio circuit, digital twisted pair line, streaming media (IP) data network line, and NC optical fiber line.
As for the hall and theatre, because the distance between the power amplifier and the loudspeaker is not too long, the direct feed mode of low resistance and a large current is generally adopted, and the transmission line requires a special horn line. As for the public broadcasting system, because of the wide service area and long distance, the high voltage transmission is often used in order to reduce the loss caused by the transmission line. Because the transmission current is small, the demand for the transmission line is not very high, and generally using the common audio line is enough, which belongs to the analog audio circuit.
Digital addressable public broadcasting system generally uses digital twisted pair lines to transmit. The system transmits audio and control signals through a twisted pair line with two cores, which not only saves the cost of installation and wiring greatly but also provides the predominant favorable conditions for the high reliability of the future system maintenance and the system operation. It has a farther transmission distance and better transmission effect.
As most schools, companies and other public places have already been covered by streaming media (IP) data network lines (LAN lines), in order to form streaming media (IP) public address system, we only need to add the streaming media (IP) public broadcasting system equipment to the original network. The original streaming media (IP) data network line can be used directly for transmission, the further wiring is not needed anymore.
Because of the large public address area and the long transmission distance of some places such as parks and communities, NC optical fiber line should be adopted for transmission, the transmission distance can reach 20-200KM, which can solve the problem that the previous public address system cannot carry out the long-distance transmission.
It is required to match the whole system, and the selection of its position should be in accordance with the reality. Generally, floral horn, indoor sound column, wall hung sound box or suspended sound box can be used indoors. Outdoor sound column, lawn special sound box, horn, etc. can be used outdoors.