Janis Heldmann, who is graduating from the Acoustics and Audio Technology major this autumn, received the 3rd Best Paper Award at the International Conference on Digital Audio Effects (DAFx) in Vienna, Austria. DAFx is a three-day annual workshop and the prime venue for presenting novel audio and music processing developments related to artistic technology.
The paper titled ‘The Role of Modal Excitation in Colorless Reverberation’ studies perceptual effects of unevenly distributed modal energy in room acoustics reverberation. The late reverberation, which results from repeated reflections from walls of a room overlapping chaotically, can also be modeled as a superposition of thousands of resonances called room modes. While earlier studies have focussed on how room modes decay over time, the present paper studies how the total sound energy influences the perceptual quality of the reverberation.
The results of this study can be directly used to design smoother artificial reverberators and improve sound quality in applications such as music production and virtual reality. You can listen to a selection of sound samples on this webpage.
The motivation of this study, which continued into Heldmann’s master’s thesis, was based on a combined interest of complex algebraic systems apparent in modern artificial reverberators, and how humans perceive similar sounds as significantly different from each other.
In his approach, he conducted listening tests of carefully tailored sound samples and those generated from novel reverberators to draw connections between mode perception and total sound energy.
This work has been advised by Sebastian J. Schlecht, Professor of Practice for Sound in VR of Aalto Acoustics Lab and Media Lab.