New Microphones Are Bringing Crystal-Clear Changes
Monday, March 31, 2008
The little black devices, the shape and size of small cellphones, have begun to appear in hundreds of Washington area classrooms. Hanging from the necks of elementary school teachers in Alexandria and kindergarten and first-grade teachers in Prince George's County, they might herald the most significant change in classroom technology since the computer, some predict.
They are infrared microphones, designed to raise the volume and clarity of teachers' voices above the distracting buzz of competing noises -- the hum of fluorescent lights, the rattle of air conditioning, the whispers of children and the reverberations of those sounds bouncing off concrete walls and uncarpeted floors.
"It makes it so much easier for the children but also for the teachers," said Lucretia Jackson, principal of Alexandria's Maury Elementary School, one of the first in the area to use the audio enhancement systems for all classrooms. All Alexandria elementary school teachers now have them. "They are no longer suffering from laryngitis," Jackson said. "They don't have to project their voices as much as they needed to do in the past."
Led by the area's longest-serving school audiologist, Frankie Mickelson, Prince George's is spending up to $1 million a year to install the systems in every classroom. The cost for the four ceiling speakers, microphones and other equipment in Alexandria and Prince George's is about $1,800 a room, a strain on tightening school budgets. But teachers have embraced them, and studies indicate they improve learning.
Electronic sound enhancement systems have been used in classes for hearing-impaired students for several decades. One of the first was developed by Claudia Anderson, a Utah advocate for the deaf with two hearing-impaired children. At a fundraiser in the early 1970s, she noticed a television reporter using a wireless microphone and asked how it worked. She started a company, Audio Enhancement of Bluffdale, Utah, that used the same FM radio technology in its speakers and microphones. But they could be used only in one or two classrooms per school because of the limited number of frequencies available.
In the late 1990s, an infrared system transmitting sound by light waves, which would allow every classroom to have wireless technology, was developed. The idea of using the technology for all students spread quickly through Utah and parts of Florida and has just reached the Washington area.
The audio systems, also sold by LightSpeed Technologies of Tualatin, Ore., and FrontRow of Petaluma, Calif., not only make it easier for teachers to speak and students to hear but also add excitement to classroom participation, teachers say. The systems include roving microphones, similar to those used by singers on television, which students use to answer teachers' questions or make special presentations.
"They love it," said Martha Walsh, a second-grade teacher at Maury. "It is kind of like they are movie or rock stars." One of her students, 8-year-old Thora Gibbs, reacted to that idea as insufficiently serious. "It's not like being a rock star," she said. "But it does help project my voice."
Classmate Catherine Daly, also 8, said she liked the microphone system "because people can hear your ideas better."
Mickelson, an audiologist in Prince George's for 38 years, lives by what she calls the signal-to-noise ratio. For teachers to be effective, their words have to be about 10 decibels louder than the ambient noise in the room. That is difficult to attain consistently with the unaided human voice, given the resistance to making classrooms as quiet as possible, she said.
The possibility of fire discourages schools from having fabric wall coverings and carpets, which could absorb background noises. Some parents also complain of carpets aggravating allergies. And architects rarely think much about sound when designing classrooms.
But about a decade ago, Mickelson said, research began to show that the microphone and speaker systems would aid the learning of most students, not just those with hearing impairments. Mickelson noticed that in college lecture halls, teachers often had microphones. "So we were doing it for adults but not for children," she said. "It didn't make sense."