Noise Reduction Systems
Unwanted noise can be distracting, confusing, and simply irritating. Sonic puts multiple Noise Reduction Technologies* to work to identify and reduce unwanted sounds. Less noise means better speech understanding and greater comfort.
Speech Priority Noise Reduction
A hearing device’s first job is to help people better understand speech. It’s a straightforward goal when everything else is quiet. However, most conversations have some kind of noise in the environment—and distinguishing between speech and noise can be difficult. Some hearing instruments use noise reduction systems that reduce sounds for comfort, but this comes at the expense of intelligibility. Speech Priority Noise Reduction, however, helps listeners clearly hear the sounds that are important.
Speech Priority Noise Reduction works to separate speech from surrounding noise by constantly monitoring incoming sounds. The system takes a modulation “fingerprint” of the signal. Sounds that are highly modulated—with a variety of high and low sounds—are most likely speech and should be preserved. Sounds that do not show modulation—like the steady hum of a fan—are most likely noise and should be reduced. By independently managing the noise and leaving the speech signal intact, Speech Priority Noise Reduction provides comfort and preserves the intelligibility of speech.
Comparison of speech and noise amplitudes for the phrase “Everyday Sounds Better” with accompanying signal-to-noise ratio (‘SNR’) for a traditional noise reduction system and Speech Priority Noise Reduction (‘SPNR’).
Impulse Noise Reduction
Impulse Noise Reduction suppresses unexpected loud sounds, like the clinking of silverware or jangling of keys. The amplification of these sounds is often rated as one
of the most uncomfortable aspects of wearing hearing instruments.
Impulse Noise Reduction identifies impulsive sounds by examining the input and checking for the following traits:
- Is the input unexpected – does it greatly differ from the average input?
- Is the input quick – is it of a short duration?
- Does the input have a high intensity – is it loud?
Once an impulsive sound is identified, Impulse Noise Reduction suppresses the sound without modifying other parts of the input that may contain important speech cues. The result is improved listening comfort without sacrificing speech intelligibility.
Soft Noise Reduction
While amplifying important speech signals is part of a hearing device’s basic function, amplifying annoying and unwanted noise shouldn’t be. This is particularly true of low-level sounds: the whirring of a fan or the soft rumble of a refrigerator. Soft Noise Reduction reduces these quiet but distracting sounds without modifying the amplification of important speech-related signals.
Wind Noise Reduction
Wind Noise Reduction makes time spent outdoors more enjoyable by preventing wind sounds from being amplified. When wind is detected, the Wind Noise Reduction feature quickly sets the lowest frequencies to an optimal omni-directional response and applies maximum attenuation across all frequencies, providing instant relief.
*Sonic products may feature one or more Noise Reduction technologies; see product specifications for details.