"Hi Kelly. I just want to say, you're one of the most amazing people I've ever met."

Whoever left that anonymous voice message, and whoever the subject of his heart is, will be able to see it light up the night sky over the Benjamin Franklin Parkway in Philadelphia.

"Open Air" is a temporary art installation that solicits messages from the public, and tranforms them into canopies of light pulsing and pivoting over the Parkway.

Artist Rafael Lozano-Hemmer has installed 24 powerful spotlights, at 10,000 watts each, along the boulevard. They react in unison to the sound of an individual voice.

"Most of the time when you see a light show in the sky, it is following a score of music. The lights are moving to the beat, or they are just moving at random, like the opening of a new shopping mall," said Lozano-Hemmer. "Here in Philadelphia, if those lights move they are reacting to the voice of someone who has sent a message through a special iPhone app or through a web page."

For example, the voice of an anonymous woman saying: "I dedicate this to Dane. He's a little boy who has cancer. Get better soon, buddy."

Or, a screaming child: "When I eat Hot Cheetos I get crazy!"

The project, a commission by the Association for Public Art, has intentions in the spirit of pure democracy. Control of the powerful matrix of light is completely given to whomever leaves a voice message on the system.

It's a highly technical undertaking, that's had its share of glitches.

This is how it works: You record a message no longer than 30 seconds via an iPhone -- sorry, no Android -- or through OpenAirPhilly.net. The system analyzes the sound of your voice, its frequency, dynamics, and volume. That message goes into a waiting list with hundreds of other 30-second messages.

When your message comes to the top of the queue, those 24 spotlights installed on the roofs of buildings lining the Parkway undulate and form patterns -- a cone, a net, a salute -- in reaction to the sound of your voice. The beams can cross 600 feet in the air, and be seen for miles.

Commanding the spotlight

Those users who leave messages in the system while actually standing on the Parkway will be prioritized to the top of the queue, and be given a personal show. Through the iPhone's GPS circuitry, the spotlight will know exactly where the user is standing and the lights will congregate their beams above that spot.

"These kind of lights are typically used for large-scale events, corporate events, Olympics, things like that," said Lozano-Hemmer, a Mexican-born artist living in Montreal. "At the Mexican border, the lights that are used are also xenon-discharged lamps. But they are used by either police authorities or by maverick groups like the Minute Men who try to search for Mexicans at the border."

Although the project wears its democratic ideals on its sleeve, literally lifting freedom of expression to the heavens -- one voice at a time -- its invasive tracking systems and military-style surveillance tools evoke less friendly uses.

"The challenge is to work with these darker technologies to create more poetic applications for them," said Lozano-Hemmer. "More critical applications that help us visualize what is actually at work in the contemporary city."

When the system launched Thursday night, the public engagement aspect was plagued with problems. Thousands of people gathered on the Parkway to hear experimental vocalist David Moss performing an improvised aria, and hip-hop artist Rahzel, the human beatbox, lay down rhythms with just his mouth and a microphone.

But the app needed to interact with the lights could not be downloaded from iTunes. Then the free wi-fi network Lozano-Hemmer installed over the Parkway went down. The evening progressed with demonstrations by previously uploaded messages (including some pulled from the sound archives of WHYY, prepared by Elisabeth Perez-Luna), but nobody was able to interact with Open Air directly.

Most of the bugs were fixed by the next day.

"Open Air" will be operating nightly until Oct. 14, with an outdoor lounge area at Eakins Oval where people can borrow iPhones from the Open Air crew. Lozano-Hemmer chose the Parkway location in part because it is a grand boulevard that does not see very much foot traffic.

A new approach to revitalization

"I spent 20 years talking to politicians who want to revitalize their city center," said Lozano-Hemmer. "Sadly what most of these politicians mean by revitalizing is putting 19th century lampposts and cobblestones and stores around. In order to revitalize, what we need to do is try something new, try something eccentric, something that interrupts the normal corporate, consumerized narratives of the globalized city."

Lozano-Hemmer had been getting heat from activist groups. Early in the planning stages, the Audubon Society approached him with concerns that the lights will interfere with birds, which get confused by bright light. The spotlights are now designed to go dark periodically, to allow birds to reorient themselves and resume their migration.

Opponents of light pollution also voiced concerns about 240,000 watts of light beaming into the night sky. The Franklin Institute came to the artists' defense, says the added light is a drop in the bucket compared with normal urban light emission.


Video by Lindsay Lazarski