Washington (CNN) -- A new anti-crime technology has reached downtown Washington -- but so far, it's getting a mixed reception.

A device called the Mosquito, which makes a high-pitched noise aimed at driving away young loiterers, has been installed near a Metro entrance just down the block from the Smithsonian's National Portrait Gallery.

"I thought it was really annoying," said a passerby named Conrad, during a break in the noise. "It gave me a headache."

Some pedestrians looked around bewildered until they found the source of the noise, which sounds like an electronic beeping; but most people who walked by showed no reaction at all. The Mosquito's sound has to compete with the everyday urban cacophony of traffic, the Metro, and a couple of video billboards pitching ads.

The building's management company, Transwestern, says the new device was installed in the past few weeks in response to loiterers. The area is a popular strip at night, but a month ago, police say, a fight that began at the Gallery Place Metro station around 11 p.m. grew to a brawl involving 50 or 60 teenagers and young adults. Five people were hospitalized with injuries.

A local youth advocate is critical of the device.

"This isn't the best solution," said Judith Sandalow, whose Children's Law Center is just down the block. "We need to have better programs for youth, we need to engage them in activities."

Transwestern issued a statement saying its goal is to ensure "a pleasant and fulfilling experience to each visitor."

But Conrad, who declined to give his last name as he passed by, said the cure might be worse than the disease. "I probably wouldn't shop at any of these shops if I heard it again. It doesn't just target the people who are causing the problems."

Another passerby, who said he was 15, told CNN, "I think we should be able to hang out where you want, as long as it's not rambunctious or disruptive."

Mike Gibson, whose company is the distributor for the Mosquito, said the device is particularly effective on youths ages 13 to 25, because that is the age at which humans can hear the highest pitches.

"When a youth hears the sound, they find it extremely annoying and will leave the area in a few minutes," he said. "The sound is benign, will not harm anyone, and is very effective in moving loiterers from an area."

But Transwestern said it has set its Mosquito at a pitch that can be heard by all ages, not one that targets teenagers in particular.

For anyone curious about whether their ears can hear the noise, there are samples of the sound at various pitches on the company's website, http://www.movingsoundtech.com.