Unlike room acoustics, dealing with sound propagation inside rooms, building acoustics occupies with sound propagation between rooms in buildings resp. from outdoors to indoors. The structures of the building are excited by airborne sound or impact sound (walking, hammering or the like) particularly to bending waves and radiate airborne sound to the adjacent rooms.
Research at the ITA mainly deals with modelling and auralisation of sound insulation.
A model for auralisation of airborne sound insulation was developed and embedded in a commercial software for calculating sound insulation in buildings. Thus it is possible for the user to evaluate the influence of changes in the building products on the hearing impression.
At the moment, a similar model for auralisation of impact sound insulation is developed. The goal is to obtain the sound signal perceived by a listener when a force is injected in the adjacent room (e.g. a walking person in the upper room). The model is a little more complex because of the dynamic interaction between the source (walker) and the excited structure (floor). To consider this interaction the force and impedance of the source and the impedance of the structure have to be known.
The main advantage of auralisation is the possibility to get subjective impressions of subjects. Normally, sound insulation is characterised by single number ratings which only consider the sound pressure level. With auralised signals it is possible to take psychological and psycho-acoustical factors into account. Thus, a more hearing related rating of sound insulation can be achieved by new methods for single number ratings.