Original title: Let the general secretary’s speech sound in your ears!Headquarters Audio Group makes good sounds for you. Source: CCTV News Client
On the morning of July 1, 2021, BeijingTiananmen SquareIn the square, the celebration of the 100th anniversary of the founding of the Communist Party of China was grandly held here. More than 70,000 representatives from all walks of life celebrated the centenary of the Communist Party of China in a grand ceremony.
The main station documentary filming team lasted 2 months to shoot the whole process of preparing for the celebration of the 100th anniversary of the founding of the Communist Party of China, and recorded the touching stories behind the centennial festival with the lens.
The celebration of the centennial of the founding of the party has attracted national attention and global attention. Compared with the live audience, more people listened to the important speeches of the General Secretary through live broadcast and TV, and shared the solemn historical moment of the party’s grand ceremony and the people’s festival. This is an unprecedented challenge for the sound protection and TV relay team.
Through repeated tests again and again, the sound team gradually explored the law of propagation of sound in the field.
Zhou Fengxin, a staff member of the sound protection headquarters of the Party’s Centennial Celebration Conference: First, you come to the following (speaker), and add it to this group.
Zhou Fengxin, a staff member of the audio support headquarters of the Party’s Centennial Celebration Conference: The sound from this speaker lacks low frequencies.
Reporter: The function of this speaker is to speak to the observatory, right?
Zhou Fengxin, a staff member of the sound protection headquarters of the Party’s Centennial Celebration Conference: Yes, fix the viewing platform and record it first. For example, if we want to hit the sound at that position, if it is low now, it will hit the wall when it hits the wall. Will bring a lot of reflections, then these reflections will affect others. So we first record these sounds, and then we finally decide how to adjust.
Through the precise control of the angle of sound reinforcement of the speakers, the reflection interference of the square buildings on the sound is reduced. For the densely distributed speaker equipment in the square, the audio team adopted a partition delay method for amplification.
Zhu Feng, Executive Deputy Commander of the Audio Security Command of the Centennial Celebration of the Founding of the Party: The reading speed of sound transmission is about 340 meters per second, but the transmission of electricity is 300,000 kilometers per second, and each square is about 40 meters. The sound delay between is about 0.1 second.
Using the first row of speakers on the northernmost side of the square as the baseline, the sound team set the sound of the speakers in front of each audience square to be 0.15 seconds later than the previous row of speakers before they sounded in order from north to south. This means that the sound of the last row of speakers is about 1.2 seconds later than the sound of the first row of speakers. This ensures that no matter which square the audience sits on on July 1st, when the sound of speakers from any other position reaches his square, the row of speakers in front of him will start to sound. It is ensured that there is no sound interference between the various speakers, and at the same time, every audience on the scene can hear a clear and full sound.