Article from 2013 about crowd noise records.
MYNORTHWEST.COM
September 12, 2013 @ 5:45 pm (Updated: 4:08 pm - 9/13/13 )
The Seahawks 12th Man fans are loud and distracting to opponents at CenturyLink Field, no doubt. But they are not going to break the world crowd noise record at Sunday night's game against the San Francisco 49ers.
Paul Richardson, a former math and science teacher, is not even buying that a crowd at a soccer match in Turkey achieved the loudest roar in 2011.
During a soccer match between Galatasaray SC and Fenerbahce SC, a crowd of about 50,000 at Turk Telecom Arena in Istanbul reached a decibel level of 131.76, according to the Guinness Book of World Records.
"The idea that it happened in Turkey at a soccer match is preposterous. It's made up," says Richardson. "It's a made up number because no matter how you push it around the laws of physics apply the same for them as they do for us."
What does he know? Richardson says he studied acoustical physics and is also trained as a sound and recording engineer.
While most people, including the media, have been cheerleaders for the goal of breaking the record by having everyone scream just a little bit louder, Richardson has been doing the math.
If the whole crowd of about 65,000 at CenturyLink are cheering at about 112 decibels - the current record at the Seahawks stadium - Richardson figures each person was probably yelling at about 64 decibels.
"That's right where I expected it to be. Normal conversation is between 55 and 60 decibels," he says.
"If you're talking across the yard to a neighbor you might be around 60. Someone who is singing is around 62 decibels. Someone who is shouting is around 64 or 65 decibels, so the current noise for a Seahawks game is legitimate."
The 12th Man would have to make a huge leap to get to 132 decibels, and he doesn't believe it's possible.
Decibels are measured on a logarithmic scale, which is a way of talking about exponential increases and decreases in relative proportions to a certain reference level which is a threshold for human hearing of sound and that's defined as one decibel.
"Whenever you advance 10 decibels, from 50 to 60 decibels for example, you have to have 10 times more sound energy," he explains. "From 60 to 70 another 10 times. From 70 to 80, another 10 times. 10 to the third power is 1,000 so in absolute quantities it gets huge."
Another way to look at the exponential increase needed is to consider a different logarithmic scale we're more familiar with. The Richter Scale was developed to assign a single number to quantify the energy released during an earthquake
"The Nisqually Quake in 2001 was measured at 6.2 magnitude on the Richter Scale. For the 12th Man to make from 112 decibels to 132 decibels and break the record, it would be the same as if that Nisqually Quake of 6.2 was 8.2," Richardson says.
"I think everybody knows that a quake with a magnitude of 8.2 would pretty much wreck the city. It would be devastating. It wouldn't be just a little bit more, because it's 100 times more energy."
An increase from from 112 decibels to 122 decibels requires 10 times more power.
"Ten times more 12th Man power, which is 65,000 people. So you need 10 times that, which his 650,000 people. If you want to go another 10 decibels to 132 decibels, you need 10 times that, so that's about 6.5 million people," he says.
Instead of having an increase in the number of people, can't each person scream even louder? If yelling across the street is 64 decibels, I think I can scream louder than that.
"Each person in that case is going to have to scream at a level of about 83 decibels. That is the equivalent to a Harley-Davidson motorcycle revving its engine. That's a pretty big voice," he says. "Essentially, you'd have to scream as loud as 100 people."
Guinness experts will have a judge and a noise meter at CenturyLink Field during Sunday night's game, at the request of a fan group and Kirkland marketing company run by Former Seahawks Joe Tafoya and Kerry Carter.
Specific guidelines must be followed, some of which involve the proper microphone and where it's placed on the field.
The 12th Man will get three noise record attempts, and Tafoya wants the first one to take place when the 49ers have their first possession.
"After that, the next two attempts, I want them to be organic," Tafoya says. "If a big play happens, like a sack or an interception, those are the times I want them to be recording."
Despite his scientific and mathematical skepticism, Richardson thinks fans will achieve the "bogus" record.
"There's no way you're going to tell the fans that they failed. They will announce 'Yes we did it. We achieved the record,'" he chuckles.
He says the 12th Man should instead focus on throwing the 49ers off their game. Low voices are not as distracting as high pitched sounds.
"Do that kind of shrill whistle where you stick your fingers in your mouth and whistle," Richardson advises. "If everybody could do that, that would shake them up."
Kickoff is at 5:30 p.m. and the pre-game on KIRO Radio begins at 2 p.m
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By LINDA THOMAS
TLDR:
To add 10dB to a sound with equal loud sources you need 10X sources.
To add 20db to a sound with equal loud sources you need 100X sources.
To add 30db to a sound with equal loud sources you need 1000X sources
