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Frequency Shifting Hearing Aids: How They Work

By Zawn Villines
Frequency shifting hearing aids can help people with high frequency hearing loss hear better. Here’s what you need to know about these assistive devices.

Many people with hearing issues never try hearing aids, despite the benefits they may offer. According to the National Institute on Deafness and Other Communication Disorders, just 16% of adults between the ages of 20 and 69 who could benefit from hearing aids have tried them. There are many different kinds of hearing aids available. If you struggle with hearing loss that affects mostly high or low frequencies, frequency shifting hearing aids may greatly improve your quality of life.

What Are Frequency Shifting Hearing Aids and How Do They Work?

Traditional hearing aids function like microphones, making sounds louder. Frequency shifting hearing aids help move sounds into a frequency that is easier for the wearer to hear, Angela Shoup, PhD, FAAA, FNAP, president of the American Academy of Audiology, tells WebMD Connect to Care.

People with hearing loss, especially age-related hearing loss, often lose their hearing in higher frequencies first. This makes it harder to hear high pitched sounds, like children’s voices. 

Different sounds in language are pronounced with different frequencies. Vowel sounds have low frequencies, while consonant sounds have higher frequencies.

This means that processing of consonant speech sounds is extremely difficult [for people with high frequency hearing loss], leading to the experience of feeling like you hear sounds fine but they are muffled or difficult to understand,” Shoup says. Some people notice that the letters F and S sound muffled first.

Because frequency shifting hearing aids lower the frequency of high pitched sounds, they are also sometimes called frequency lowering hearing aids. These devices manipulate high frequencies, making them sound lower and, therefore, easier to hear. 

Two different frequency shifting algorithms were tested in a 2019 study published in Trends in Hearing:

  • Frequency transposition moves an entire set of high frequency sounds into a lower frequency. The resulting sound will be substantially similar to, but lower than, the original sound. 
  • Frequency compression compresses smaller sounds into lower frequencies. This produces more differences from the original sound than with linear transposition. 

The small study, which included just 20 participants, found that frequency transposition may have more potential to help patients with high frequency hearing loss compared to frequency compression.

Hearing Loss Can Be Treated and Managed. 

Hearing loss is not usually reversible, but doctors can treat it. Early treatment can help identify the cause and help you access the hearing aids you need. It is worth taking the time out to get the answers and treatment you or your loved one deserves. Don’t wait. Start today.