The term digital is used for most of today's current technology, from televisions to cell phones. Hearing aids today are digital, which means incoming sound is converted into a series of numbers which are then processed using mathematical equations. Digital processing enables very complex manipulation of sound, for example, to separate speech from noise. A few digital instruments are capable of 1.8 million calculations per second.
The digital technology within hearing aids allows sounds to be separated into different frequency regions, or pitches, and amplify each region selectively, depending on the hearing aid user’s hearing loss. The processing within hearing aids also enables different amounts of amplification for soft, moderate, and loud sounds, so that soft sounds are audible, but loud sounds are not uncomfortable or over amplified. Digital processing enables a natural sound quality with minimal distortion, resulting in excellent sound quality.
Digital hearing aids are programmable, meaning the hearing aid settings can be precisely fine-tuned, and special features can be adjusted for each wearer by a hearing professional, using special hearing aid software on a computer. Hearing aids are programmed and customized for both the hearing loss and the preferences of the person who wears them.
In addition to basic digital hearing aid technology, many hearing aid manufacturers offer several levels of advanced features made possible with digital processing technology. Digital hearing aids continue to advance and have become much more automatic. These hearing aids are equipped with sophisticated features for people who regularly encounter challenging listening situations. Examples of some of these advanced features, what they do and how they benefit the hearing aid wearer are:
- Directional Microphones – Two microphones on the hearing aids work together to give preference to sounds in front of the wearer and reduces sound, especially noise, from behind the wearer. This technology has been proven in research to improve speech understanding in background noise. In some hearing aids, the focus point for speech can be to the right, left or behind the person. This enhances listening benefit in difficult situations, such as the car.
- Noise Reduction -Determines if signal contains unwanted background noise and reduces the level of background noise if present. Background noise is less annoying, and the user’s listening comfort is improved in noisy situations.
- Feedback Management - Reduces or eliminates whistling that can occur with hearing aid use. Advanced technology eliminates any whistling from the hearing aid but does not compromise volume or sound quality.
- Wind Noise Reduction - Reduces the noise created from wind blowing across the hearing aid's microphone(s). Designed to improve comfort for people who spend a lot of time outdoors.
- Data Logging/Learning - The ability of the hearing aid to track and learn the hearing aid user’s preferences in various listening environments. This information can assist the hearing professional in making future programming adjustments and allows the hearing aid to adapt to the user’s preferences.
- Bluetooth Interface - Establishes a wireless connection between hearing aids and Bluetooth compatible devices such as cell phones, computers, televisions, remote microphones, etc.