Digital hearing aids promise better sound quality.
Christiane Jung started having problems with her hearing when she was a teen-ager in France. But it wasn't until nine years ago, when she left France for England, that she decided she needed a hearing aid.
Since then she has used one periodically -- but not all the time -- to help with conversations.
She lives in Lawrence now, and her hearing aid still isn't perfect.
"First of all, it increases the noise which surrounds me, and that can be annoying, especially in restaurants," said Jung, who is 52. "The sound is somehow metallic and my own voice changes. It's not as soft as I usually perceive it."
Soon, however, she's going to test a new kind of hearing aid that came on the market this year.
Two companies, Widex and Oticon, are marketing digital hearing aids that are supposed to deliver much better sound quality and automatic volume control.
"The older type of hearing aids have more distortion," said Barbara Jozsa, an audiologist at Lawrence Otolaryngology Associates.
Like the new digital hearing aids, some analog hearing aids are also programmable. That means they can be modified to amplify specific wavelengths of sound to match a person's hearing loss. In older analog hearing aids, the volume must be controlled manually so users have to adjust the volume throughout the day, depending on whether they're at home, in the car, at work or in a movie theater.
The new devices can be programmed to more closely match a person's hearing loss, and they sample sounds 504 times a second to adjust the amplification.
"You can tailor systems a lot better than other devices in the past," Jozsa said. "Patients can put them on in the morning and take them off at night, and the digital sound processing has really good sound quality."
Hearing aids cost from $600 to $2,400. The new digital aids are at the high end of the price range, and health insurance generally doesn't cover the expense.
Some have likened the sound quality in the older analog hearing aids to that of AM radio.
Given that one out of four Americans over age 65 suffers from hearing loss and that older Americans constitute the fastest growing segment of the population, the application of digital sound technology to hearing aids was long overdue.
"Hearing aid technology is still improving, but it hasn't been great," Jozsa said.
Across all age groups, 25 million Americans suffer some form of hearing loss. The most common cause is the aging process. Loud noises and some diseases can also damage hearing, and some cases of hearing loss go unexplained.
Christiane Jung's greatest troubles come when trying to differentiate words or syllables that sound similar, like the letters 'm' and 'n' when spelling names. She hopes her English-speaking skills will improve with a better hearing aid.
"I would like to be able to understand the very first time, and to make out the subtle differences between sounds and to understand also the end of phrases, when the voice drops," she said.
"In a conversation, very often the funny thing comes at the end and I always miss it, so you are missing something all the time. It's very, very frustrating."