Audio DesignLine Blog
Audio awareness - a winner at the 2010 FIFA World Cup
Rich Pell
6/22/2010 2:59 PM EDT
learn more about audio acoustics and processing? But it has, thanks to the controversy over a loud and raucous African blowing horn - called a vuvuzela - used often and enthusiastically by thousands of spectators at the games to express support for their teams.
The problem is that not everyone's a vuvuzela fan. Announcers at the games and players on the field have complained that the noise interferes with their activity, while other spectators at the games have expressed concerns over possible hearing damage. And fans around the world watching on TV have been annoyed both by the loudness of the sound on the broadcasts, and by the degree to which it interferes with the clarity of the audio commentary.
The resulting attention to this issue has been enormous. It's produced a slew of news reports describing the acoustic characteristics of the vuvuzela, myriad solutions and how-to videos for "de-vuvuzelating" the sound on your TV, and even a hilarious new Downfall meme video ("Hitler and the vuvuzela at the 2010 FIFA World Cup").
The instrument at the root of all this is about 2 ft in length and made of plastic. It produces sound mainly at about 235 Hz and 465 Hz and is capable of sound pressure levels up to 130 dB. (Listen to the sound of a vuvuzela (4 s audio sample).)
Some of the offered solutions include vuvuzela noise reduction software plugins from commercial professional audio companies like Prosoniq and Waves. Others are simple DIY audio filtering solutions - typically using notch filters - that anyone can use on their PCs. Just a few of the examples of the latter include the following how-to YouTube videos:
The audio engineering behind the filtering solution presented in the last video is even described in an article at Physorg (How audio engineering helps tone down vuvuzela disruption). Finally, there's even a guide to vuvuzela fever for those who still wish to learn more about the instrument and various filtering solutions.
Comments, questions or suggestions? Email me at rich.pell@verizon.net.
Related links:
Acoustics and Psychoacoustics Applied - Part 3: Filtering and equalization
Acoustics and Psychoacoustics: Introduction to sound - Part 1: Pressure waves and sound transmission | Part 2: Sound intensity, power and pressure level | Part 7: Analysis of sound waves | Part 8: Using filters to analyze frequency spectra
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kendallcp
7/4/2010 8:49 AM EDT
I must say that I was surprised at how long it took broadcast audio engineers to figure out how to attenuate the contribution of the vuvuzela from the 'ambient feed' coming out of the stadia. I didn't get around to checking out the sound on an FFT analyzer - believe it or not, I had better things to do on work days than watch the football - but it certainly sounded as if most of the energy was concentrated around a particular tone. putting in fairly gentle notch filters at the tone and the first few harmonics would be an obvious first step. A particularly easy way to achieve this would be to sum the signal with another version delayed by 4.26ms. This sum has nulls in the response at 235Hz and multiples - though perhaps not broad enough to eliminate everything.
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Frank Eory
7/12/2010 1:11 PM EDT
On the very first day of the World Cup, when I watched part of the broadcast, I felt like the broadcaster was going to have to very quickly come up with a solution for the vuvuzela problem. It took them awhile, but they finally did.
Nice to know that a sports series and the traditions of a particular nation's fans could make such a contribution to the appreciation and understanding of audio engineering by so many non-engineers!
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Jimelectr
8/1/2010 2:39 AM EDT
Well, you caught my attention with the tagline about the FIFA World Cup providing a venue for millions of people worldwide to get a (slight) education on audio and acoustics. Yeah, to an EE, a notch filter is a no-brainer for such a narrowband interferer as the vuvuzela. As far as soccer (sorry, that's football to the ROW) goes, I'm not a big fan, but a lot of my coworkers are, and I found it more entertaining to watch them than to watch the game! (Since my employer, Broadcom, makes chips that go into DTV's, we have many screens scattered about our campus, and some especially large ones set up in the cafeteria during the World Cup). The expressions on their faces and hearing dozens of people shout, "Ohhh!" at the same time was priceless!
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ReneCardenas
8/30/2010 2:28 PM EDT
As a soccer fan I found this audio background sounds as part of the celebration.
Since soccer is still remains marginalized in USA, this is a minor inconvenience for USA viewers that did not get filtered audio. Since Soccer World Cup is a tournament that is only played every 4 years, in my eyes it is not a significant issue.
USA TV broadcasters need to become more aware of every intrinsic detail required to broadcast a sanitized version of every sport. Since it appears that most TV viewers do care too much for the front-row live experience!
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