Ball-level acoustics: Close-ball audio mixing

Photo: DFL/Getty Images/ Sebastian Widmann

26. September 2023  – Football fans watching games on screen want to feel as close to the action on the pitch as possible. This not only applies to the image captured by the cameras but also to the sound of the game. The acoustic backdrop for the video is provided by many microphones arranged around the pitch and controlled automatically based on live position data.

The perfect sound for the action

Delivering a captivating football experience means providing the right sound, as well. In Bundesliga stadiums, a total of 17 microphones are arranged around the pitch to capture the acoustic surroundings: the boot hitting the ball, the shouts of the players, the referee’s whistle. But not all the mics must be “on” at all times to create a realistic acoustic experience: At any given time the microphones closest to the action on the pitch are most relevant, while those located further away are less important. Adjusting the microphones accordingly used to be a tedious manual process, keeping the sound engineers busy pushing the slides on the mix panels up and down in response to what was happening on the pitch. The rapid and often quite unpredictable player action made this an energy-sapping task.

Today real-time digital match data control the sound

The availability of digital match data in real time has revolutionised live broadcasting, including sound mixing. Every movement on the pitch is automatically captured by tracking cams set-up inside the stadium. Their live tracking data, available instantly, is not only used to generate official match statistics and analytical graphics. Today it is also fed to the mc² console for sound mixing. Depending on where the live tracking data identifies relevant action on the pitch, the microphone input faders are moved up or down. For the fans watching at home, this creates a sound experience that is literally always at the ball level and is matched perfectly with the scene displayed on screen.

Photo: DFL/Getty Images/ Sebastian Widmann

More excitement for fans, more creative time for sound engineers

This innovative audio production system has become the standard for Bundesliga broadcasts. It was developed by Lawo AG and ChyronHego in collaboration with DFL and Sportcast. ChyronHego, a USA-based broadcasting technologies and services specialist, generates the official tracking data capturing the exact positions of all 22 players on the pitch, the ball and the referees in real time for use by various processing systems, including sound engineering. Lawo AG, a manufacturer of media infrastructure and production systems for broadcasting headquartered in Rastatt, Germany, developed the software application KICK which provides the interface between the tracking data and the sound mixing console. KICK decides in a continuous process which microphones are best suited to reflect the player action acoustically, sending appropriate signals to the console.

This new sound technology not only benefits the fans by creating a more realistic match experience on screen. It is also a great help for the sound engineers who no longer have to hand-operate the microphone faders. Instead, they are free to focus on perfecting the overall sound aesthetics.