Professional Audio Products And Engineering Applications
The development of professional acoustics and engineering applications in China can be divided roughly into several stages in chronological order:
1. Early stage of liberation to the pre-Cultural revolution
There are few new professional theatres and stadiums in this period, with Beijing as an example:
Built in 1959, Beijing Workers Stadium;
The Beijing workers ' Gymnasium, which was built in 1961 for the 26th session of tennis;
Tianqiao Theatre was founded in 1953, is the first theater after the founding of New China;
The Capital Theatre, affiliated with the Beijing People's Art Theatre, was delivered in 1955.
Most of them are clubs or halls of society or units. At that time the theatrical group performance basically does not use the sound reinforcement, but the meeting uses some simple "enlargement" usually uses the radio, the Front class tube amplifier "one machine".
2. The Cultural Revolution to the early stage of reform
During the Cultural Revolution, the "model play" in order to "highlight the heroes" in the performance began to widely use sound, then the audio equipment is basically domestic products. It can be said that the "model play" for theatrical groups to use the sound amplification "opened the precedent."
1974 the fourth Ministry of Machinery Industry to cooperate with the central Orchestra abroad performance, organized 6 provinces and cities 18 manufacturers in the time of six months to develop, production of our first professional audio products, later someone called it "zero breakthrough." The representative equipment is: Cr1-1, Cre-3, Cre-5 microphone, 20 watt Two-frequency speaker, DK-100 tube amplifier and 16-way front, and so on, the equipment was later adopted by the vast number of theatrical troupes. This set of professional audio product development and production for the subsequent development of domestic equipment has laid a preliminary foundation, can also be said to be our country's professional sound system product development "primary stage."
Around 1982, foreign professional audio products began to enter China's representative brands are: Peavey, Ev and JBL and so on.
1984 before and after the complete set of imported professional audio system products began in China's theaters such as: Shong Chinese Theater, Xinjiang Autonomous Region People's Hall, Shenzhen municipal Government Hall.
At the beginning of 1987, the Joint Research Group of the Ministry of Electronics and the Ministry of Culture conducted a comprehensive survey of the enterprises in Beijing, Tianjin, Jiangsu, Shanghai and Hangzhou to produce professional audio (including machine, microphone and loudspeaker). The rise of the professional audio industry in the same year in August by the Ministry of Electronics Industry led the establishment of the China Electronic Audio Industrial Association seventh chapter, namely "Professional Audio Branch", at that time, the member units are: The Electronics Industry Institute, Beijing, Shanghai, Jiangsu, Tianjin and Hangzhou, 14 of production units (mixer, amplifier, etc.) of the enterprise composition. "Professional Audio Branch" on the domestic equipment at that time less varieties, the general level of low and the use of foreign exchange and other issues put forward many positive suggestions for the development of professional audio equipment in China has played a positive role in promoting. At the same time, also for China's professional audio industry to train talent, accumulate experience, the introduction of foreign advanced digestion technology and products laid a good foundation.
We know that the development of high-level devices (microphones, speakers, etc.) depends on new materials and advanced processing technology, the same high level of the machine (mixer, amplifier, etc.) development depends on the new devices and advanced processing technology. That era because of China's industrial base is relatively backward professional sound system product development to withstand greater constraints, for example: transistor power amplifier due to the lack of a dedicated high-power output tube can only be used 12-inch black and white TV line output tube to replace; the treble in the speaker is still stuck in the aluminum material, but also does not have the use of titanium alloy material conditions and so on.
From September 22, 1990 to October 7 in Beijing, the 11th session of the Asian Games, Beijing to build and rebuild stadiums 26. It was later increased to 33 for a variety of reasons. The launch of the Asian Games venues in the second half of 1986, at this time from the Asian Games held 4 years. Because of the serious lack of financial funds at that time, all new and rebuilt sports venues of the sound system equipment, especially the main system is mostly domestic products.
It is necessary to point out that this period of our country's professional audio system products have made great strides, farewell to the early era of "electron tube age." The traditional "large cylinder" has been replaced by two-frequency, three-frequency, full range speaker, constant directivity and broadband acoustic column; simple "front" is replaced by a mixer with a marshalling output, and so on.
3. Reform and opening-up to the late 20th century
This stage has two distinct characteristics, one is the reform and opening up after the "popular music" and various types of concerts in China's rapid rise, the second is the new and rebuilt throughout the country's theaters, halls, stadiums and other facilities developed rapidly, thus driving professional audio system equipment and engineering application needs. Engineering application of a large number of international brands of professional audio system equipment, this period of sound system is still in the analog system era.
4. Enter the 21st century phase
Since the 21st century, because of the improvement of China's comprehensive national strength, the rapid development of culture, sports and other construction undertakings, the application of professional sound system engineering has formed an "unprecedented great development" period. The development of culture and sports construction is an important aspect of the application of professional sound system. Examples are as follows:
(1). "Grand Theatre", represented by the National Grand Theatre
This year has just completed the Beijing China National Theatre and in recent years many provinces and cities have built a large number of areas of the "Grand Theater" or "Art center", such as: Hangzhou Grand Theatre, Guangdong Dongguan Grand Theatre, Shanghai Oriental Art Center, Wuhan piano Taiwan Grand Theatre and the Qingdao Grand Theater under construction, etc., and some recent television stations are being built in the TV studio theater, such as: CCTV Studio Theater, Beijing TV Studio Theater and Jiangsu TV Studio Theater.
(2). Beijing 2008 Olympic Games
Since 2001, Beijing bid for the 29th Olympic Games in 2008, 31 new or rebuilt stadiums are needed. 12 of them are new venues, 11 are for the expansion of the stadium, and 8 are temporary venues.
(3). An average of four-year national games
As of 2005, China has held ten national games, on average every four years, each national games also led to the construction and development of regional sports facilities. Take the nineth session and the ten National Games as an example:
The ninth national Games from November 11, 2001 to November 25 in Guangdong Province, the new main venues 11, renovation, maintenance venues 45, a total of nine games will provide 122 games, training venues. The new Guangdong Olympic Sports Center Stadium, which can hold 80,000 people, bears the opening ceremony and athletics of the ninth games.
The National Games of the ninth session were held in Jiangsu Province from October 12, 2005 to October 23.
22 new venues in the provincial 17, city level 5. The maintenance and renovation of provincial stadiums mainly focus on the sports center of Wutai Mountain in Jiangsu province. Nanjing Olympic Sports Center is the main arena of the tenth national Games, including main stadium (including warm-up field), gymnasium, swimming pool, tennis center, News Center. There are 60,000 seats in the stadium for the opening, closing ceremonies and athletics and football competitions of the 10 games.
(4). Average biennial Chinese arts festival
By the end of 2007, China has held eight Chinese arts festivals, on average every two years, each Chinese festival has driven the construction and development of regional cultural facilities. Take the seventh session and the eight festivals in China as an example:
The Chinese Arts Festival was held in Zhejiang Province from September 10, 2004 to September 26, and it was required to provide a total of 42 venues for the festival, with 21 new and reconstructed performances. Hangzhou Grand Theatre, Shaoxing Grand Theatre, Ningbo Grand Theatre, Jiaxing Grand Theatre are all new theatres.
The Ninth Chinese Arts Festival was held in Hubei Province from November 5, 2007 to November 20 in Wuhan. A total of 35 new and renovated venues have been provided for this festival. The Qin Tai Theatre, which is invested 1.57 billion yuan by Wuhan municipal government, is the main venue of the Chinese Art Festival.
To sum up, so many cultural, sports facilities need to be equipped with a large number of professional audio systems. Since the 21st century, the international well-known professional audio system equipment flooded into the Chinese market, almost covering the international most advanced products, can also be said to have achieved "full international standards." For example: Germany Stagetec, Germany Lawo MC82, Switzerland Studer Vista Digital mixer, the United States Meyer Sound, Eaw, R, JBL, EVI, Germany K, Deb Sound and the French L. Acoustics speaker and line array loudspeaker system; The United States Evi, crown with DSP processor power amplifier and so on.
Today, the rapid development of science and technology, electro-acoustic systems and equipment upgrading quickly, new technologies and new products are emerging. At present, in the period of alternating simulation technology and digital technology, digital audio network shows its superiority more and more than traditional analog system. We know that the signal noise of digital system is high, the dynamic range is big, the system function is powerful, the system expands ability and the system integrates control ability is strong. The signal takes the fiber as the carrier carries on the transmission, not only the information quantity is big and the anti-interference ability and the reliability is strong, usually the multimode fiber and the single-mode fiber transmission distance are 1Km and 100Km respectively, each fiber can transmit hundreds of audio signals. Therefore, the traditional analog electro-acoustic system is gradually replaced by digital system, this trend has become the inevitable development of science and technology
Digital audio Network, which is the main body of digital mixer, has been widely used in radio and television recording and broadcasting System. In the field of sound reinforcement, there are already theatres and stadiums (such as the National Grand Theatre, Bird's Nest stadium, etc.) to design the use of digital audio network system, in order to secure and ease the use of most of the simultaneous configuration of a simulation system to backup, the overall accumulation of experience is not much.
The main problems needing attention in the digital network system are: the security and reliability of the system, the amount of redundancy, the transmission rate and bandwidth, the performance and the level of DSP processor and the rationality of the optical-brazing network topology. In addition, the selected digital mixer in the operating interface, should have analog mixer on-site tuning simple and intuitive, in short, to 'choose the right' products and reasonable design.
In recent years, there has been a power amplifier with built-in digital signal processor, which synthesizes the functions of digital processing, network control, system monitoring and amplification, and has a strong module-type expansion capability. Typical brand products are: Evi, CSC and Crown-It network power amplifiers. This new type of power amplifier is usually accompanied by analog and digital two input ports, for the sound reinforcement system to provide a convenient connection, especially in the system at the same time, digital mixer and analog mixer use. The use of the power amplifier with DSP in the system further simplifies the configuration of the system signal processor, which can be completed one time by the usual two A/d, d/A (modulus, digital module) conversion, which is helpful to improve the system signal transmission quality and system reliability.
Into the 21st century, our domestic professional sound system products have made great progress and improvement, which is encouraging and gratifying. Some of our production of microphones, speakers and power amplifier manufacturers in the introduction of foreign advanced technology, production lines, product quality control and testing methods have done a lot of work. Some manufacturers export the total value of professional audio products each year in billion or hundreds of millions of yuan. The current domestic professional audio products such as: microphone, loudspeaker, power amplifier and signal processor and other product performance consistency and reliability has been better resolved, can completely replace the imported products to meet the majority of the stadium library fixed installation sound reinforcement system.