How the NFL uses fake crowd noise to make it sound real

New York Post

Viewers were stunned on Sunday when Philadelphia Eagles QB Carson Wentz was booed off the field in an empty Philly stadium. Turns out the boos were only played on TV, not in the stadium. NFL Films gives NFL broadcasters crowd noise from past games that are unique to each stadium as part of a project to enhance the TV experience during the pandemic. "During the project, the NFL hired local people, who were fans of the team in each market and provided them a unique briefcase of sounds," reports the New York Post's Andrew Marchand. "So, for example, the Jets’ system is completely different from the Giants and operated by a different person.....NFL Films happened to have just completed a four-year project in which they had collected crowd noise from all the NFL stadiums....Films needed to take hundreds of hours to strip the crowd noise from the in-stadium music, public address, etc. that was recorded as they made their prototype which was built off M&T Stadium, home of the Ravens. The enhanced broadcast noise is all the result of an arduous process that began in June with a combination of NFL Films, NFL broadcasting and Robert Brock from the Conservatory of Recording Arts and Sciences in Arizona, among those working together."