Silencity

The Truth About Noise

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Electric cars must make noise after September 2019:

car-bmw

“Quiet Car” rule will require all electric vehicles to make noise, so pedestrians can better hear and avoid them.  CNET.com reports on the long-awaited National Highway Traffic Safety Administration rule requiring auto manufacturers to add waterproof, temperature resistant sound generators to hybrid and electric vehicles sold after September 1, 2019.  Referred to as vehicle warning sounds, the sound will be automatically activated when a car travels at speeds below 18.6 miles per hour.

Electric and hybrid cars are noticeably quieter than cars powered by an internal combustion engine.  This fact drew the attention of advocates for the blind and visually impaired a decade ago, ultimately leading to the passage of the Pedestrian Safety Enhancement Act (PSEA) of 2010.  The PSEA is intended to reduce the risk of harm to blind and visually impaired pedestrians, as well as cyclists, or anyone unable to hear the very quiet approach of these cars, by requiring electric and hybrid cars to emit a minimum added sound.  The issue regarding this requirement is complex and contentious, and it has generated a lot of research and extended discourse both for and against added sound.  Many electric and hybrid cars have used added sound for years; samples of some sounds can be found online.

A significant concern is that some automakers see the need to comply with the rule as an opportunity to invent branded sounds, while critics of branded sounds would prefer sounds as similar as possible to a vehicle engine, noting that discordant or unusual sounds could actually create confusion.  In addition, environmental advocates and soundscape preservationists have expressed concern about adding more noise to an overburdened soundscape.

One problem with reaching a sensible solution is that the instructional videos produced by industry tend to show cars and pedestrians interacting in open spaces, but real world experiences are more likely to occur in busy parking lots or residential streets.  Measures such as traffic calming and slow zones could result in a growing number of areas where driving below 20 miles per hour would be the norm in order to improve safety for pedestrians, cyclists, and drivers.  One thing is clear, vehicle engineers must incorporate these details into the planning of current and future warning sounds.

Asked about branded sound design, Jeanine Botta, who runs the Green Car Integrity Project blog, said that she hopes sound designers will follow the rule’s requirement that sound be recognizable as a motor vehicle in operation, and let go of branding concepts.  “Our attention is already stretched to its maximum potential.  No pedestrian – or cyclist or motorist – should have to quickly process and interpret any sound, especially one intended for safety.  If a sound is the least bit discordant, it runs the risk of being misinterpreted and ignored.”

Automotive product developers considering new and improved added quiet car sound should include industry outsiders in the research and development process.  Consultation with environmental psychologists, environmental health researchers, acoustic ecologists, and soundscape preservationists would be a step in the right direction.

 

Anti-social miscreant nabbed by cops

Photo credit: El Segundo Police Department

Photo credit: El Segundo Police Department

Joseph Serna, L.A. Times, reports that “praise poured onto El Segundo Police Department’s Facebook page from ecstatic residents” this past Sunday, November 13th.  Why?  Because “'[t]hey found the air horn guy!!’ wrote Jenn Birch.”  Yes, John W. Nuggent, pictured above, outfitted his “little blue four-door, 2006 Chevrolet Aveo” with “an air tank with hoses connected to a device near the car’s gas pedal.”  When the officer tried the car’s horn, he heard what sounded like the horn of “a big truck or train.”  Nuggent then admitted that he was the guy who had been driving down the middle of the street for six weeks, waking up the residents with his horn, all to annoy one specific resident with whom he had had a dispute.

Nuggent was arrested on suspicion of disturbing the peace.  We suspect the prosecutor should get an easy conviction.

 

 

OSHA announces hearing-protection technology contest winners

lightbulb_innovation

Four inventors have been recognized by the Occupational Safety and Health Administration, the National Institute for Occupational Safety and Health, and the Mine Safety and Health Administration for their innovations in developing technology intended to combat work-related hearing loss.  The winning designs include a custom-fitted earpiece that offered workers protection, wearable sensor technology that detects noise levels, and an interchangeable decorative piece that attaches to silicone earplugs.

Link via @jeaninebotta.

Potential relief for those living near wind farms:

wind-turbines

Owl-inspired wing design reduces wind turbine noise by 10 decibels.  Some people living near wind farms have complained about health problems caused by the turbine noise.  While the debate continues as to whether the noise adversely affects human health, relief may be on its way.  Science Daily reports that a team of researchers studying the acoustics of owl flight have been working on pinpointing the mechanisms used by many species of owl that allows them “to hunt in effective silence by suppressing their noise at sound frequencies above 1.6 kilohertz (kHz) — over the range that can be heard by humans.”  The researchers wanted to use those mechanisms “to improve human-made aerodynamic design — of wind turbines, aircraft, naval ships and, even, automobiles”  And apparently they have succeeded in using owl feathers “as a model to inspire the design of a 3-D printed, wing attachment that reduces wind turbine noise by a remarkable 10 decibels — without impacting aerodynamics.”

 

 

Let’s find out, shall we?

sports-car

Can electric sports cars be sporty without any engine noise?  The author of this piece, Jordan Golson, The Verge, suggests the answer is no, because he thinks noise = fun:

Not only does a noisy engine give a visceral thrill, knowing that there are thousands of tiny explosions happening to keep you going, but it just sounds awesome. It would be a shame to lose it, and carmakers know it. Bloomberg says Porsche has been looking at artificially inserting noise into the cabin, perhaps via the stereo like some other manufacturers have done, or amplifying the high-pitched hum of the electric motor.

I don’t know what the answer is, but a world without the roar of a Dodge Challenger Hellcat is a world that’s just a little less fun.

And so the rare opportunity to reduce the overall noise level in our soundscape will likely be ignored, as carmakers will rush to spend big bucks adding unnecessary noise to electric cars because engine noise “just sounds awesome.”  Sigh.

 

Queen’s guitarist, Brian May, complains to council

over noisy leaf-blowers.  Yes, it not just a U.S. problem, leaf blowers are fraying nerves in London, too.  The Telegraph writes that May, “[f]amed for his loud rock anthems, [] has used his blog to criticise Kensington And Chelsea Borough Council for dismissing his road sweeper and replacing him with six people armed with noisy leaf-blowers.”  We understand May’s frustration at dealing with ear-splitting noise, especially when he found, in the end, that “the state of the road was worse after the men had attempted to clear it.”  May laments “the awful noise of the blowers, dust and leaves being blown into my garden, and petrol fumes,” adding that |they are creating a horrible intrusion into our lives.”

The Telegraph notes that May isn’t the only celebrity who hates leaf blowers, writing:

In May, actor Tom Conti appeared on a television show to moan about the racket from the machines, insisting they were ruining his peace and quiet.

He said: “It’s very, very loud and unnecessary. If these people can’t stand the sight of a leaf then it’s not a leaf-blower they need, it’s a psychiatrist.”

Point, Conti.

It not just humans who can’t tolerate noise:

dogs

FDA approves first drug to help dogs deal with noise-related anxiety.  Anyone who has been around a dog when fireworks are going off know that loud noise frightens them.  According to the Daily Mail, the fear of loud noises is common “for the 70 million dogs in the U.S. and their owners.”  The fear is not insignificant, as “[d]ogs are sometimes so frightened they jump through windows, destroy doors while trying to escape a room or run into traffic and get hit by cars.”  So rather than require that people use silent fireworks as is being considered in one Italian province, the U.S. responds in typical fashion by focusing not on the source of the noise, but rather on the poor creatures who suffer because of it.  Introducing Sileo, a $30 syringe filled with doggy anti-anxiety drug that will calm your pooch for about two or three hours.

So why not mandate the use of silent fireworks or other noise control measures instead?   $30 X 70 million dogs = 2.1 billion reasons the market prefers Sileo to reasonable noise mandates.

The cause of this noise is not a mystery:

not-quite-whales

Whales Would Probably Like Us To Make Less Noise In The Ocean.  Alasdair Wilkins, Vacativ.com, writes:

Whales’ haunting songs already suggest a complex form of communication beyond our easy understanding. Now it turns out we only knew half the story, as whales might also communicate through low-frequency vibrations they send through the water. Biologists only recently discovered this ability, and it might mean all our shipping and undersea drilling have been making a ton of unwanted, vibration-heavy noise for whales.

xxx

Yet another mystery noise:

ice-sheet

Canadian military probes mysterious Arctic pinging noise.  The BBC reports that the “Canadian military has investigated a mysterious pinging sound coming from the sea floor in a remote region of the Arctic.”  The sound has also been described as a beep or hum.  Whatever the source, the noise is scaring away animals, which is a problem for the indigenous people who live and hunt in the area.  The Canadian press has put forth a number of explanations including the following:

  • It is a sonar survey conducted by a mining company

  • It is being generated on purpose by Greenpeace to scare wildlife away from the rich hunting ground

  • It is caused by military submarines

Deepening the mystery is that mining companies, Greenpeace, and the military have either denied responsibility or have claimed no presence in the area where the noise has been heard.

Given how quickly Arctic ice has been melting, one wonders if the sound could have a wholly natural source like deep ice splintering or calving.  Thoughts?