Sound Systems Are Divided Into (4) Main Systems (According To The Purpose And The Nature Of Use) as follows:
- Public Broadcasting System
- Indoor radio system
- Outdoor broadcasting system
- Conference Systems
Now, we will show a brief for each system and a detailed explanation for each one will be posted later.
1- Public Broadcasting System : see fig (1) & (2)
fig (1) fig (2)
Public address system for hotels, commercial buildings, ports, airports, subways, schools provide background music and radio programs. In recent years, public broadcasting system also caters to emergency broadcasts, can be linked with the fire alarm system. The public broadcasting system control functions more. If all call radio broadcasting and electoral functions, work force capabilities and priorities for the right to broadcast functions. Speaker load multiple and scattered, long transmission lines. To reduce transmission line losses, generally 70V or 100V constant voltage with high impedance transmission. Pressure not ask for much, the sound quality to the tone-based alt.
2- Indoor radio system: see fig (3)
indoor radio systems are the most widely used system, including various types of theaters, stadiums, dance halls and so on. It is highly specialized, both non-verbal reinforcement, but also for various performances, the use of very high quality requirements, system design should not only consider the problem of electro-acoustic technology, but also issues related to architectural acoustics. The room´s shape and other factors have a greater impact on sound quality.
fig (3) fig (4)
3- Outdoor broadcasting system: see fig (4)
Broadcasting system is mainly used for outdoor stadiums, railway stations, parks, art squares, musical fountains. Service area is characterized by its large area, space is broad. Large background noise; sound to direct sound transmission main; to Demand high sound pressure level, if high-rise buildings and other reflective objects surrounding the speaker layout and quite reasonable, sound waves formed by multiple reflections more than 50ms delay will cause double or multiple acoustic sound, in severe cases echo problems affecting the voice clarity and sound image localization. Outdoor sound system is also affected by climatic conditions, wind direction and impact of environmental disturbance.
4- Conference System: see fig (5) & (6)
With domestic and international exchanges increase, in recent years, conference calls, video conferencing and digital conference system (DCN) has developed rapidly. Conferencing systems are widely used for conference centers, hotels, groups and government agencies. Conference system including conference discussion system, voting system, simultaneous interpretation system and TV conference system. Requirements of audio and video (image) system simultaneously, all using the computer control and storage of session data.
fig (5) fig (6)
In the next topic, I will explain the first system; Public Broadcasting System.