Modern stadium sound system solution
1. The main features of the electro-acoustic system of modern stadiums can be summarized in three aspects:
★ Pay more attention to the sound effects of the auditorium and venue of the venue;
★ In order to meet the needs of the opening ceremony, closing ceremony or performance of large-scale sports competitions, more attention should be paid to the corresponding "mobile" sound reinforcement system;
★ Electroacoustic systems pay more attention to the use of digital network transmission and control systems.
2. The electro-acoustic system of the stadium mainly includes
1. Meet the live sound reinforcement system of sports competitions
2. Mobile sound reinforcement system that meets the opening ceremony, closing ceremony and large-scale performances
3. Automatic priority broadcast system that satisfies multi-level broadcasting (including emergency broadcast)
4. Digital networked signal transmission and control system
5. Power amplifier and signal transmission fault automatic detection system, etc.
III. Basic requirements for the sound reinforcement system in the stadium
1. The regular use of sports venues is sports competitions or mass gatherings. Therefore, the basic requirement for sound reinforcement systems is to first ensure the intelligibility (or clarity) of language sound reinforcement. It seems that it is not easy to have a good hearing in the implementation of the stadium audience (or most of the audience).
2. Use of sports venues If there is a large-scale sports event opening ceremony, closing ceremony or large-scale high-level performances, then the sound reinforcement system is equipped with a high-quality "mobile system" in conjunction with the original "fixed" installation system. It will be better and more economical.
3. The audience of the modern sports venues is different from the traditional "audience", and more is to support the "fans" cheerleaders of the team. The atmosphere of the sports competition is warm. However, for the sound reinforcement, the "background noise" level is increased and random, and should be paid full attention in the design of the sound reinforcement system.
Stadium sound reinforcement system solution
4. Performance specifications of stadiums
1. Performance specifications of the stadium
The "Acoustics Design and Measurement Regulations for Gymnasiums" is edited by the China Academy of Building Research and approved by the Ministry of Construction. It has been implemented since March 1, 2001. The main contents include: general rules; architectural acoustic design; noise control; sound reinforcement design and acoustic measurement (see JGJ/T131-2000, J42-2000 for details).
The competition hall is basically divided into a comprehensive gymnasium competition hall; a swimming pool competition hall and an ice rink hall.
2. Acoustic characteristics of the stadium
The acoustic characteristics of the stadium currently have no written norms in China. Recent data from the World Federation of Football Federations (FIFA) and the German Football Association (DFB) indicate that the steady-state sound pressure level of the stadium auditorium is about 105 dB.
Requirements for the acoustic characteristics of the main sound reinforcement system for new or rebuilt stadiums in the 2008 Beijing Olympic Games;
Sound pressure level: 95dB for normal use; 106dB for maximum sound pressure level (emergency broadcast).
Transmission frequency characteristics: the language uses 100Hz ~ 5KHz ± 5dB;
The music uses 100Hz to 15KHz ±5dB.
Language clarity: Fast language transfer index RASTI ≥ 0.5.
It should be pointed out that although the stadium is a non-enclosed space, it is very important that it cannot be treated as a free sound field in the sound reinforcement design. Most of the stadium auditoriums have "singing sheds" with sound reflections. A typical stadium can accommodate tens of thousands of seats. The reverberation time of the stadium will be as long as 5 seconds, and the reverberation time when the audience is full will also be It takes about 3 seconds. Therefore, full attention should be paid to the design of the sound reinforcement system.
V. Sound reinforcement sound field control is the foundation of sound reinforcement system design
Sound reinforcement belongs to the category of applied acoustics, and whether it is indoor or outdoor sound reinforcement, it cannot be separated from the acoustic environment (or sound field) in which the sound reinforcement is used. The final effect of sound reinforcement is the embodiment of the comprehensive effect of sound reinforcement and electroacoustic sound. Therefore, the basic problem of sound reinforcement system design is acoustic problem. It is the analysis and design calculation of sound reinforcement sound field on the basis of sound construction.
If a sound reinforcement sound field is evaluated from the acoustic characteristics of the sound reinforcement system, there are mainly the maximum sound pressure level, the transmission frequency characteristics, the sound field unevenness and the sound transmission gain. If a sound reinforcement sound field is evaluated from the sense of hearing, there are mainly the clarity of the language and the clarity of the music, and the sound quality effect of the "many attributes" of the sound.
Whether it is indoor or outdoor sound reinforcement, the sound field of the sound reinforcement has more or less acoustic interference, perhaps this is inevitable. The existence of sound field sound interference will affect the speech intelligibility and the clarity of the sound, which will detract from the sound quality of the sound reinforcement. Modern sound reinforcement design is no longer "satisfied" in the general sense of sound pressure level and sound field unevenness, but pays great attention to the sound interference problem of sound reinforcement sound field, in the design to try to reduce the sound interference to a minimum, this is modern The focus of sound reinforcement design.