Natural Own Voice by Active Occlusion Cancellation

The Occlusion Effect

The occlusion effect occurs when the ear is closed, e.g., by hearables or headphones. The own-voice sounds boomy and like talking in barrel. To get a feel for this effect, you can put your fingers into your ears while talking.

This effects occurs as air-conducted sounds are attenuated by the earpiece and body-conducted sounds are amplified in the closed cavity.

We solve this problem by Active Occlusion Cancellation. For this our algorithms use an inner and an outer microphone, as typically available in ANC headphones. The microphone signals are processed and a cancellation sound is emitted by the loudspeaker.

Algorithm integration

Our algorithms are well tested in real-time demonstrators using Analog Devices ADAU 1787 integrated circuits. Consumer listening test have proven a significant improvement of the own-voice perception.

Our algorithms operate using basic signal processing capability of the ADAU 1787 with optimized design.

Award winning technology, backed by University

Our technology has be awarded the annual RWTH Innovation Award.

It is presented together with Analog Devices, a leading global high performance analog technology company, at the ISE 2020 in Amsterdam 11-14 Feb, 2020 – one of the leading international trade shows in the field of audio/video and system integration.

Key Features and Advantages


  • Patented and award winning technology to digitally opening the ear
  • Algorithm ported to ADI ADAU 1787
  • No additional hardware for ANC-ready headphones


  • Significantly increases comfort and all-day wearability
  • Solves the consumers dilemma over open vs. closed designs
  • Transforms voice calls and interaction with voice assistangs


  • Increases ASP and differentiation
  • New unique premium feature for hearables
  • Selecting an Alpha Partner Q1. Production ready Licensing Program in 2020

Market Potential

The self-perception and comfort play a major role for all-day wearability of a hearable or headset. Our technology creates a significant improvement on these aspects.

It creates a key differentiation and completely new user experiences in various markets.


General Information

RWTH Aachen University
Institute of Communication Systems
52074 Aachen, Germany