Soccer hooligans could be silenced by a new sound system that neutralises chanting
with a carefully timed echo.
Stadiums could use the technique to defuse abusive or racist chants, say the Dutch researchers behind it. The echoes trip up efforts to synchronise a chant, neutralising an unwelcome message without drowning out the overall roar of a crowd.
Sander van Wijngaarden, who researches human acoustics at the Netherlands Organisation for Applied Scientific Research in Delft, began working on the technique in 2004 after several Dutch soccer matches were blighted by abusive chanting.