A vuvuzela is tuned - to use the term loosely - at the B flat below middle C, and has a similar frequency to speech tones, says Trevor Cox, president of the Institute of Acoustics. This makes it particularly tricky for broadcasters to tune out, as to do so would dampen the commentators' voices - and not in a good way.
Here's one solution...
"I'm looking at its wave patterns and there are at least six very strong harmonics in there. It would sound really horrible to notch these out - if one coincides with the vowel sound e, you won't be able to hear the -es in the commentary. It would sound unnatural."
To "notch out" is sound engineer speak for making a sound filter to block a certain frequency.
Various online vendors claim to sell vuvuzela filters - such as a 45-minute MP3 noise-cancelling track to play during each half - and a German computer programmer has posted instructions online - in German - for building your own using a soundcard-equipped computer and specialist software. But buyer beware, says Professor Cox.
več:
http://news.bbc.co.u...ine/8738604.stm
http://news.bbc.co.u...ght/8741086.stm
Prispevek uredil/a: greenhorn, 15 junij 2010 - 01:14 .
