Chip Audette and the folks at Tympan has developed a fully open source hearing aid development platform.
Hearing aid technology has been closed technology with access only available to those working in the industry and Chip set out to change that. What began as an experimental project has now become Tympan, an open source hearing aid development platform.
The Tympan platform uses a Teensy 3.6 and the Digital Signal Processing (DSP) capabilities of the Teensy Audio Library to implement dynamic range compression – amplifying quieter sounds while not making louder sounds any louder. Chip has a great explanation of the need for dynamic range compression in this blog post. He follows it up with details on how he implemented it in this blog post.
The Tympan units are affordable devices that allows users to program and customize their own hardware to best suit their hearing needs without having to go to a technician each time an adjustment is needed.
The Tympan hearing aids are OSHWA Certified. Code, schematics and KiCad files are available on GitHub.