Good Good Good Reverberations

Engineeing student, Nathan Willson, with sound measurement instrument

By Thomas Bevan

Sound may be impossible to see, but a study at the Centre for Interactive Research on Sustainability (CIRS) is tracking it through a technique called Auralization, a developing area in acoustical engineering. By creating and reproducing sound fields using computer data, it is making sound modeling more realistic and precise.

This is one of the projects in the Sustainable Building Science Program (SBSP), located in CIRS, which explores lasting ways of building human habitats. The program creates an inter-disciplinary and collaborative environment for professional training and research that is applied to the design, creation, operation and monitoring of buildings to promote health, occupant satisfaction and have a low ecological footprint.

Virtual sound representation is still developing but already there are multiple applications. “By creating virtual acoustic modelling techniques to answer questions with regard to speech privacy and noise control in sustainable building design, we can provide architects and engineers with qualitative ideas of what to expect when planning buildings for optimal sound performance,” says Nathan Wilson, an Electrical Engineering student from the University of Victoria, on a co-op placement, working with supervisor Murray Hodgson, Director of the Acoustics & Noise Research Group.  “Constructing an experimental building environment is too expensive to do in real life. By creating a virtual model of the building in question, you can manipulate it exactly the way you want and make predictions about parameters that would be unrealistic or too costly to measure within a real model.”

The first stage in the study determined what geometric and material properties of the area in question were important to establishing the parameters of the model. Next, a base model was created to measure reverberation, speech intelligibility, and speech privacy. The testing point was to construct a virtual silencer in a natural-ventilation opening above a partition in one of the area’s offices, where sound was escaping and disturbing the inhabitants in the other room. Then using auralization, changes were measured in the base parameters. Future applications of this research are timely indeed given the trends towards 3-dimension virtual reality.

“The film industry is putting significant resources into enhancing the realism of viewer experience in movies such as Avatar, or the more recently released Hugo,” Willson says. “However, sight is only one sense. Sound is an equally important part to the overall virtual experience and this is where we will see more development in coming years.”

SBSP is accepting work term students, as well as undergraduate students, graduate students and postdoctoral fellows that have been first admitted into home programs in Engineering, Science, Architecture, Health and Social Sciences and Forestry. The SBSP is also offering courses for anyone interested in learning about sustainable building science.