As you come up the escalator in the Gallery Place / Chinatown Metro in Washington, D.C., you are serenaded by loudspeakers playing Mozart, Chopin, Beethoven. But why? It turns out that certain sounds really annoy teenagers and cities are now using them to keep young people out of public places. As an effort to control crime or reduce vandalism, though, the use of high frequency noises, classical music, or nature sounds raise questions about whether cities are in fact serving their younger citizens well.

In Washington, D.C., the Smithsonian Museum first had the idea of blasting classical music from outdoor speakers at night. The city then ran with it and began offering a selection of classical hits at the busy Gallery Place / Chinatown Metro station, where teenagers had been congregating and robberies were occuring.

In addition to the new classical soundtracks, a "mosquito" device, which emits a "shrill noise at 18 KHz, a high frequency that only young people can hear," was also introduced as another sound layer. According to Greater Greater Washington, the devices, which were put in place by a local development company, "are wrong and may even be illegal," and they have called for logging a case with the D.C.  human right commission to force the developer to stop. The local Web site thinks its unfair anyone under 25, even those not out to cause trouble, to now face noises as obnoxious as a chalkboard being scratched. "Toddlers, teenagers, and young adults waiting for the bus or emerging from the Metro will now have to endure a shrill screech purposely aimed at annoying them and driving them away." 

The bigger issue for them may be a lack of accessible public spaces for teenagers in cities. Greater Greater Washington bemoans that teenagers have been pushed out of all public areas: "Before the age of suburban development and private shopping mall, cities always included grand public spaces for relaxation and socializing. Sometimes these spaces were formal, grassy parks and sometimes these places were paved plazas like the piazzas in Italy. Unlike private shopping malls, which serve as the de facto gathering places in most suburbs, public streets, squares, and parks in cities are by their virtue open to the public." Indeed, part of Chinatown's charm as a public place may be that it's filled with young people out on the town. Instead of driving teens away, they argue that curfew times could be made earlier, or police patrols can be beefed up to deal with kids committing crimes.

Communities, developers, or institutions seem to be noises to keep trouble teens away because they can't afford the cops or security guards they need. In a recent example, a regional transit system in Portland, Oregon, has been adding opera to the mix at light-rail stations, bringing down loitering in the process. The Huffington Post writes: "At one station, an aria from Bizet's 'Carmen' serenaded commuters waiting to board. 'There's no one that just hangs around,' said Scott Nielsen, who has met the train at the stop for 18 months. Before the music 'they wouldn't get on the train, that's how you'd know they were [loitering].'" For Lt. John Scruggs, a local policeman who created the program, it's a success: he points to lower crime levels and a sense of "feeling safer" on the platforms.

However, the long-term effectiveness of these noises may be in doubt. The Huffington Post queried Denis Crispo, Portland's assistant city commissioner, who argued that "as a crime reduction strategy, it may work for a short period of time, but the criminals always adapt to police strategies. It really doesn't have a lasting effect." Vandals particularly annoyed by the music are also just ripping out the speakers. 

Teens may also soon have new variation to contend with. In Lancaster, a town in California, a crime-ridden stretch now has 70 speakers blasting the birdsong of robins, wrens, tits, and blackbirds. "The warbles and twitters, mixed with soft synthesiser tones and water sounds, is broadcast five hours a day." British sound engineer Julian Treasure, whose firm has created soundscapes for clients such as Nokia and Harrods, said the birdsong works by reducing cortisol and adrenaline. Apparently so, bird sounds he added in lavatories at BP service stations "contributed to a 50 percent increase in customer satisfaction." 

Still, birdsong may actually be better than classical music and certainly better than the awful mosquito devices. The Los Angeles Times writes that noises' effectiveness as a annoyer may be tied to the neuro-biological responses people have when they hear something they don't care for. "When people hear music they don't like, their brains suppress the production of dopamine — a neurotransmitter that regulates pleasure and other emotions — which puts a damper on their spirits."

In contrast, birdsong may actually stimulate positive effects in everyone instead of just annoying some. The UK is financing a three-year research study on the benefits of being exposed to birds singing on people's moods. The Guardian writes that the lead researcher will "recruit subjects through social media and examine the effect of birdsong on their brains and behaviour, as well as testing whether recorded birdsong – played on an iPod for example – could have the same impact as listening to birdsong in cities and in the countryside."

Now if communities would only invest in safe, accessible places designed for teenagers. What would also be nice: Instead of piping in birdsong via speakers, how about creating public green spaces that actually attract real live birds.

Image credit: Gallery Place / Chinatown Metro Station, Washington, D.C. / Fivesixzero::Erik Hess. Flickr