MSc thesis project proposal

Active Acoustic Channel for Dynamic Hearing Protection

Project outside the university

Dynamic Ear Company

Nowadays there are various products in the hearing domain such as Hearing Protection Devices (HPD’s), hearing instruments, headphones, hearables etc. which protects, enhances and enables users towards normal or better hearing experience. They consist of different kinds of sound outlets / nozzles which allow the sound to travel from the sound producing, controlling and filtering units to the eardrum. These devices are placed at different positions in and around the human ear canal. When securely fit they create a closed ear canal which induces an “occlusion effect”. Vibrations caused by talking, chewing, walking, etc. are then directly reflected to the tympanic membrane due to the closed off ear canal. The user perceives these vibrations as “hollow” or “booming” echo-like sounds. Occlusion effect makes loud and unnatural sounds of the own voice and chewing based on bone conduction in the ear canal. On the other hand, when there is loose fit (an open system) natural sound is transferred to the ear, eliminating the occlusion effect. In an open system, the user may hear less of the bass and low frequencies. For environments where the noise is high, a closed fitting system is more preferable. The noise can be passively blocked by an earplug and there is a better control of the sound that reaches the ear such as less noise and better directional hearing which increase the intelligibility. However, the occlusion effect generates unnatural sound.

Due to the above mentioned some of the circumstances, there is a need for a system/module combined with an appropriate controlling unit which can accordingly adopt to these changes in accordance to the external environmental desired conditions in order to create a hassle free and pleasant end user listening as well as protection experience.


Therefore, we would like to develop an acoustic module (valve and actuator combination) which will fulfill the specific requirements. Main challenges:
  • To research, validify different basic actuator and valve principles which can have the potential application towards different product modules and subsequent uses cases.
  • To research, develop and propose a preliminary concept idea for a module (actuator + valve + driving unit) to be implemented in AAC.


  • Background of Acoustics along with Sensors and Actuators.
  • Experience with FEA modelling and analysis.
  • Capable of demonstrator building, analysis and validify.
  • Report documentation and converging towards conclusions.


prof.dr. Paddy French

Bioelectronics Group

Department of Microelectronics

Last modified: 2019-02-14