Keep Empty NFL Stadiums Roaring On TV
While many professional sports have resumed play in different parts of the world and are now being broadcast live with no fans in attendance, everyone was waiting to see what the National Football League (NFL) in the U.S. would handle the challenge. Pumping in artificial crowd noise has played a huge part in recreating the live event experience for fans watching at home.
League representatives said they had been monitoring what other leagues had been doing regarding crowd sounds but wanted its football games to have a distinctly NFL sound and feel. Since the NFL crowd-sounds are for broadcast use only, the venues are being provided with basic, though venue/team-specific, ambient crowd-sound files that will play continuously through PA systems at around 70 dB.
To ensure a consistency across its 32 teams, the NFL is supplying each team with a portable kit for enhancing crowd noise. Some stadiums are allowing minimal fans to attend, so the use of artificial audio won’t be used as much, while others are not.
NFL broadcasts this season are using what they call “enhanced” crowd sound, generated with a custom kit that includes Audiokinetic’s Wwise authoring software—which is typically used for interactive media and videogames. This allows “audio-sweetener mixers” to access and mix sounds collected from each NFL stadium over the past four years. The unique sounds were captured by NFL Films, the league’s media arm, which had been collecting team and venue audio for postproduction of its TV specials and other uses.
The Wwise software is used to manage four channels of crowd sound through a four-channel Mark of the Unicorn M4 interface and a Korg nonoKONTROL2 MIDI controller. The system offers five levels of intensity that mixers can choose from as they follow the action on the field. In addition, mixers can lay three levels of positive- and negative-reaction crowd sounds atop the ambience tracks. These sound files are launched with a single button on the screen and play and then fade as required, always resolving to the ambience tracks as the base sound. In order to avoid monotony for fans listening at home, the system randomly selects audio from hundreds of different clips and smoothly transitions between them.There are also separate sound files for specific reactions, such as generic applause, cheers, and boos. A bank of sound files called “extras” are available with specific chants and cheers for the teams playing each game.
A function called “peak extender” allows the mixers create sustained intense cheering to follow extended action, such as a long interception run down the field. These can be held as long as needed and will let the audio track revert to original ambient levels.
The system used by the NFL was built by Robert Brock, director of education, Conservatory of Recording Arts & Sciences, who is serving as a freelance consultant for the crowd-sound system.
The highly portable NFL audio kit is packaged with laptops, USB interfaces with four analog outputs each, and various accessories in a road case. Each kit is specific to a team, complete with each team’s chants and songs and with ambient sound taken from its venue during and between games in years past.
Before being used, the sound files underwent extensive editing and scrubbing to delete unwanted sounds, like profanity and game-specific calls and whistles. They were then broken into broad categories —positive and negative reactions, for example — and then into more-specific ones. The NFL team built a separate library for each team, and the league has hired an operator that is specifically assigned to each team. They configured 32 team kits in road cases with dual systems in them for redundancy and backup.
The road cases, however, are for transport to the stadium. The crowd sound is operated by the home team for each game. Although the league has made efforts as part of its operator training to avoid using crowd sounds as part of a team’s defensive strategy — boosting volume levels to obscure quarterback calls, for instance — the crowd sounds in each stadium will be operated from the home team’s perspective.
Crowd-sound system operators—there are 64: one main mix person and one backup per team—are chosen from a pool of freelance professionals who have worked for the league or NFL Films and are local to the city the team is in.
Due to the varying success of other professional leagues—like the Bundesliga in Germany that have been adding crowd noise for several months—the coverage of sports in an empty stadium is going better than most expected. TV ratings are at their normal levels and the quality of play has not diminished in any way. Some production values have been altered to fit the situation: like the use of less cameras and low camera angles and wide shots to hide the fact there are no fans.
Some have tried replicating crowds with graphics systems but it’s the audio that is making the difference.