Adding Clearcall to current technology is quite straightforward and requires only add-on software for existing devices.

The software was originally developed for use in cell phones, but Clearcall introduced distortions that people with normal hearing found distracting. That's when Furst-Yust started applying the methodology to hearing aids.

'It takes some getting used to,' she said, 'but people who have been wearing hearing aids all their lives have no problem getting the most from Clearcall. And we can train the newly hearing impaired in a quick introductory session.'