NEW YORK • Car horns, sirens, drilling, jet overflights and restaurants where diners have to yell to be heard - New York is one of the loudest cities in the world.
But the most populous metropolis in the US - "The city that never sleeps" - has launched an experiment to provide it with the technology to dial down the volume and address noise pollution.
The five-year, US$4.6 million (S$6.4 million) project - the brainchild of researchers at New York University (NYU), working with residents and city hall - is using machine learning technology and sensors to build a sound library.
The idea is to record the full panoply of noises in the city of 8.5 million residents and use artificial intelligence so that machines can recognise sounds automatically, ultimately giving the authorities a way to mitigate noise levels.
"It is like living in the middle of a soccer stadium sometimes," says filmmaker Gregory Orr. "Even the squirrels have to chirp louder in order to be heard over the din."
NYU associate professor of music technology Juan Bello, head of the "Sounds of NYC" project, says noise is "consistently the No. 1 civil complaint" to the city's 311 hot line for non-emergency services, instituted in 2003.
Researchers have installed the first sensor boxes, which transmit data through Wi-Fi, on NYU buildings in Greenwich Village. They are now installing sensors across Manhattan and Brooklyn at spots selected for their diverse sounds. By the end of the year, there should be 100 in place.
It is like living in the middle of a soccer stadium sometimes.
MR GREGORY ORR, a filmmaker who has lived in New York for 19 years.
"There are plenty of studies that show noise has a tremendous impact on health, both short and long term," says Professor Bello, citing heart conditions, hearing loss and hypertension, which then have a significant economic impact.
Educational performance is also shown to suffer among children subjected to high noise levels.
In Manhattan, the effects are amplified by skyscrapers, which form "canyons of sound" and make everything louder.
"A lot of the sounds that you get in New York would not be so loud in other places, because of the specifics of the topology of the city," Prof Bello tells AFP.
That was the concept from which the project was born, and it is being financed by the National Science Foundation.
The sensors are programmed to record no more than 10 consecutive seconds to avoid eavesdropping on conversations and posing confidentiality problems.
Researchers hope to index thousands of sounds which, with the help of New Yorkers, will be carefully annotated and help computers identify the source of nuisance sound immediately.
It would then be over to the city to do what it can to limit it.
The problem is clear. But the solutions might still be some way off.
How, for example, do you deal with something as short-lived and unpredictable as honking?
"We have to get more creative," says Prof Bello.
Today, it can take the authorities five or six days to deal with a noise complaint, and requires the intervention of one of 50 specialist inspectors, he says. After so long, the problem has often disappeared.
New York may not be the only loud city in the world, but Prof Bello calls it "a perfect laboratory" to test solutions that can be adopted and transferred "to many other places in the US and around the world".