The gymnasium is a building for indoor sports competitions and physical exercises. Gymnasiums can be divided into competition halls and practice halls according to the nature of use; according to sports, they can be divided into basketball halls, hockey halls, track and field halls, etc.; according to the size of the body, they can be divided into large, medium and small, generally divided according to the number of seats in the audience China now calls large-scale sports halls with more than 8,000 auditoriums-small-scale gymnasiums with fewer than 3,000, and medium-sized gymnasiums in between.
Sound quality design of multifunctional gymnasium
1. General requirements for acoustic design of multifunctional gymnasiums
The multifunctional gymnasium has not yet been put into use, and the echo in the room is very long. There is basically no way to hear the language clearly. What should I do? The architectural acoustic conditions of the multi-purpose stadium's competition hall should ensure that the language is clear. The auditorium and the competition venue in the stadium hall should not have any sound quality defects such as echo, tremor echo and sound focus. When dealing with sound absorption, reflected sound and avoiding sound defects in the multi-purpose gymnasium competition hall, natural sound sources and sound reinforcement speakers should be used as the main sound sources.
The acoustic design of the multifunctional gymnasium mainly includes three parts: acoustic decoration design of the multifunctional gymnasium, sound system design of the multifunctional gymnasium, and noise reduction processing design of the multifunctional gymnasium.
2. Design of the reverberation time of the stadium
Reverberation time is one of the most important indicators of multi-functional sports venues. It is directly related to many acoustic indicators such as language intelligibility, language transmission index, and music clarity. Appropriate reverberation time of the gymnasium can give the audience a good listening environment and can pay more attention to the game. If the reverb of the multi-purpose stadium is too short, it sounds very dry, lacks intimacy, and it is easy to make people tired. If the reverb of the multi-purpose stadium is too long, the language intelligibility is low, and the audience cannot accurately hear the voices of the athletes and commentators on the scene, and it will also affect the electro-acoustic system of the stadium, such as howling of the electro-acoustic system. It can be seen that the good reverberation time of the gymnasium is important to the stadium.
According to the People's Republic of China Industry Standard JGJ/T131-2000 "Gymnastics Acoustics Design and Measurement Regulations", the reverberation time of 500~1000Hz and the reverberation time of each frequency relative to the 500~1000Hz reverberation time are recommended for the full hall and swimming hall competition hall The ratio of the ringing time should adopt Table 1, 2 and Table 3 respectively.
For the skating hall with figure skating function, the reverberation time of the gymnasium competition hall can be designed according to the reverberation time of the comprehensive gymnasium competition hall with a volume greater than 80000m3. The reverberation time of special halls such as ice hockey hall, speed skating hall, tennis hall, track and field hall, etc. can be designed according to the reverberation time of the natatorium.
The reverberation time should be calculated for the six frequencies of 125, 250, 500, 1000, 2000, and 4000 Hz according to the formula, and the calculated value should be one digit after the decimal point.
T60=-
Where T60——reverberation time (s);
V-room volume (m3);
S—— Indoor surface area (m2);
——Average indoor sound absorption coefficient;
m——Air defeats attenuation coefficient (m-1).
3. Acoustic absorption and reflection treatment of multifunctional gymnasium
Sound-absorbing materials or structures should be provided above the competition hall of the multi-purpose stadium.
The glass windows around the competition hall of the multifunctional gymnasium shall be provided with curtains with sound-absorbing effects.
Multifunctional gymnasium The gable or other large-area walls of the competition hall should be treated with sound absorption.
The low walls and stands of the multi-purpose gymnasium should be equipped with sound-absorbing structures, or control the tilt angle and shape.
4. Noise control of multifunctional gymnasium
(1) General requirements for multi-purpose gymnasium and indoor background noise
The noise control of the multi-purpose gymnasium competition hall and related rooms should be taken from the aspects of overall design, layout and sound insulation, sound absorption, sound attenuation and vibration isolation of the building.
Multifunctional gymnasium The background noise of the competition hall and related rooms shall not exceed the corresponding background noise limit.
The impact of noise from multi-function gymnasiums on the environment shall comply with the provisions of current national standards.
When the multi-function gymnasium competition hall, VIP lounge, sound reinforcement control room, TV commentator room and sound reinforcement broadcasting room are unoccupied, under normal operating conditions of ventilation, air conditioning, dimming and other equipment, indoor noise should comply with Table 4 Provisions.
Room background indoor noise limits
Match hall NR35
VIP Lounge NR30
Sound reinforcement control room NR35
Sound reinforcement studio NR30
TV commentator room NR30
(2) Noise control and other acoustic requirements of multifunctional gymnasium
In the competition hall of the gymnasium, the use of rest corridors and the like to isolate external noise interference. The lounge is suitable for sound absorption and noise reduction.
The weighted sound insulation of the maintenance results of the VIP lounge should be determined according to its ambient sound.
The partition wall between TV commentator rooms should have the necessary weighted sound insulation.
V. Design of lighting and sound engineering for multi-function gymnasium
Acoustic design and material requirements of multifunctional gymnasium
1. Design of multi-function stadium lighting system (design of stadium lighting system)
(1) The lighting system should be designed according to the requirements of relevant national regulations and standards.
(2) The main hall of the venue is a basketball and volleyball court, and the auxiliary hall is a gymnasium and taekwondo venue. The lighting of the venue must meet the relevant requirements of JGJ 153-2007. The use function of the main building is grade Ⅱ, and the standard lighting value is level Ⅱ; the use function of the auxiliary hall is grade Ⅰ, and the standard lighting value is level Ⅰ.
(3) The bulbs and rectifiers are imported from Philips. Other lamps should comply with national standards.
⑷, glare level and stroboscopic effect comply with national standards;
2. Design of multi-purpose stadium sound system (design of multi-purpose stadium sound reinforcement system)
⑴. The sound system should be designed according to the requirements of relevant national regulations and standards;
⑵, generally sports sound reinforcement system;
(3) The design of the sound system meets the requirements of the relevant clauses in JGJ/T131-2000, and the sound reinforcement characteristic index is level two.
The electro-acoustic design of the multifunctional gymnasium consists of three parts: general requirements for system design; system equipment selection and configuration (including each sub-system: voice sound reinforcement, performance sound reinforcement, broadcast sound reinforcement, etc.); and acoustic design of the control room. The second item above is the focus.
According to the Ministry of Standards "Measurement Rules for Acoustic Design Section of Gymnasium", the sound reinforcement system of the gymnasium should include the following 7 systems:
(1) Sound reinforcement system for the auditorium;
(2) Sound reinforcement system for the competition venue;
(3) Checking and calling system for lounges, driving ranges and workplaces of athletes, coaches, referees, medical staff, etc.;
(4) Background music and broadcasting system to the room where the audience rests;
(5) To the broadcasting system near the entrance outside the hall;
(6) Higher-quality mobile sound reinforcement system for cultural performances;
(7) Other systems, such as a mobile music replay system for gymnastics competitions. They can be used online or independently.
According to the use requirements of the multifunctional gymnasium, the electroacoustic design of the gymnasium should include the following points:
(1) Must have an independent control and switching sound reinforcement system in the stadium, audience seats, rest hall and other functional rooms;
(2) The stadium must have a mobile sound reinforcement system for the opening ceremony, closing ceremony and literary performances;
(3) The gymnasium must have a time-series broadcasting system for emergency disaster reporting that can automatically switch over emergency powers, automatically increase the sound level of the broadcast, and evacuate according to prescribed procedures and flow directions;
(4) It is recommended to set up audio relay interface terminals of radio and television stations.
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In the standard of "Measurement Regulations for Acoustic Design Section of Gymnasium", the characteristic parameter indexes of multi-purpose stadium sound reinforcement system design are divided into 3 levels, each level has the maximum sound pressure level, transmission frequency characteristics, sound transmission gain, sound field unevenness, system The five characteristic parameters and requirements of noise, and the requirements for characteristic parameter indexes of small and medium-sized multi-purpose gymnasiums are generally considered to be "three levels" from the perspective of economy, practicability, and disturbing people. This is because, if the stadium is located in a residential area, the maximum sound pressure level cannot be too high to avoid sound leakage and disturbing the people. The frequency transmission characteristics are narrower than the "first-class" low-band bandwidth. The 250Hz-4kHz attenuation is allowed to be +4/ -10dB, in the frequency band where the speech spectrum energy is concentrated, it can ensure higher speech intelligibility, and the sound transmission gain is only 2dB lower than the "first level". The unevenness of the sound field is only 2dB lower than that of the "first level". The requirements of the three levels of system noise are the same. The maximum sound pressure level will not be too large. In addition to avoiding disturbance to the people, the number of speaker systems and amplifiers is also reduced, which can be saved. A lot of money.
Transmission frequency characteristics, sound transmission gain, and sound field unevenness are mainly problems of sound design, which will not be greatly affected by the system and equipment. The circuit frequency response of the sound system is at 20/80Hz, ~1.6KHZ/20KHZ, 3dB. Therefore, "level 3 is the preferred solution for the sound system transformation of the multi-purpose gymnasium.
The specific expression of the design requirements is:
(1) There is sufficient loudness in the auditorium of the multifunctional gymnasium;
(2) The layout of the speakers in the multifunctional gymnasium should cover the entire auditorium and the playing field, try to make the sound field uniform, and there should be no dead zones;
(3) The multi-purpose gymnasium has clear listening conditions, good sense of direction and program fidelity;
(4) The sound system of the multifunctional gymnasium should have sufficient stability and power margin;
In order to meet the above requirements, refer to the “Level I Indicator of Sound Reinforcement System for both Language and Music” specified in the standard “Level I Indicator of Hall Sound Reinforcement System” issued by the former Ministry of Radio, Film and Television. Design of the following technical indicators:
(1) The maximum sound pressure level (steady-state quasi-peak sound pressure level in the empty field) The average sound pressure level in 125Hz-4KHz is greater than or equal to 102dB.
(2) The average sound pressure level of the transmission frequency characteristic between 100Hz and 16KHz is 0dB, and it is allowed to be greater than or equal to +/-3dB in this frequency band.
(3) Sound transmission gain The average value of 125Hz-4KHz is greater than or equal to -10dB.
(4) The unevenness of the sound field is 1KHz, less than or equal to 6dB at 4KHz.