Noise-makers 'won't rattle players'
The official noise-makers for next year's World Cup in Brazil will be significantly quieter than the vuvuzela horns that caused so many headaches in 2010, researchers say.
The new instrument is a rattle called the caxirola, and it creates sound pressure levels similar to normal conversation.
Researchers from the Federal University of Santa Maria in Brazil have told the Acoustic Society of America that it would take about 2,000 of the maraca-like caxirolas to emit the same noise level as one vuvuzela.
In South Africa, throngs of fans playing vuvuzelas created a deafening roar during matches.
The incessant buzzing from the long, skinny horns was so loud that players on the field had a hard time communicating and many TV viewers initially thought there were reception problems.
"The caxirola is not so dangerous as the vuvuzela for the people who are going to be in the stadiums," said Bernardo Murta, one of the researchers.
There may, however, be another problem with the caxirola that has nothing to do with volume.
After it was introduced at a match in Brazil this year, hundreds of disgruntled fans hurled the plastic instruments on to the field when the game became a blow-out.