The math behind the magic – how Widex creates the perfect match between users and their hearing aids
Most people think about hearing aids as devices that work by simply amplifying sounds –
like turning up the volume on your stereo. In reality, the job of a hearing aid is slightly more complicated.
Living with a hearing loss
Every hearing loss is unique
The human ear detects sound across a wide range of frequencies – from the deepest, rumbling base to high pitched, squealy tones.
When people suffer from hearing loss, not all frequencies are affected in equal measure. Someone may have a hard time hearing sounds in certain frequency areas while having normal or even excellent hearing in others. This is why hearing loss is individual.
Because hearing loss typically develops slowly and in varying degrees across frequencies, it may take some time, even years, before the affected person realizes that he or she needs hearing aids.
The perfect fit
A good hearing aid can provide the right amplification across different frequency areas and different situations. But before the user can use the hearing aid, it must be given the right settings.
This is a process called fitting, typically carried out by a trained hearing care professional.
- First, the hearing care professional tests the user’s hearing in order to create an audiogram – a detailed chart that maps out the individual hearing loss.
- This information is then put into the hearing aid using a special piece of fitting software, enabling it to provide the right amplification.
- Finally, the hearing care professional verifies the fitting.
Trust, but verify
At Widex, the software used for fitting is called COMPASS GPS. It compares the actual output of the hearing aids plus the user’s audiogram against a complicated mathematical formula called a fitting rationale.
The purpose of the fitting rationale is to verify that the hearing aid is doing its job, matching the user’s exact needs while staying within certain tolerance limits.
More fitting rationales, more flexibility
Each hearing aid manufacturer has its own, proprietary fitting rationale, sometimes called fitting rules or fitting prescriptions. And around the world different universities and organizations also have their own versions. All doing the same job but in slightly different ways.
Recently Widex’s fitting software, COMPASS GPS, was updated to include two globally acknowledged fitting rationales alongside Widex’s own fitting rationale, providing hearing care professional with more flexibility and the end users with hearing aids that do a great job.