Tools and Methods for Product Sound Design of Vehicles

Interior vehicle sound is an important factor for customer satisfaction. To achieve an optimized product sound, subjective evaluation methods as well as analysis and prediction tools must be combined to provide reliable information relevant to product quality and comfort judgments. Toward this end, the European project OBELICS (Objective Evaluation of Interior Car Sound, BRITE-Euram 96-3727) was devised. It was carried out between 1997 and 1999 by a consortium of two European car manufacturers, three engineering companies active in automotive sound evaluation, and two universities. The main idea behind the OBELICS project was to understand the basis of sound perception and associated descriptive language and to derive tools for objective evaluation. Within the project, a vehicle interior sound database and ‘psychoacoustic dictionary’ were developed, and three subject-centered methods for the evaluation of interior car sounds were investigated. The three methods include Semantic Differential (SD), Multidimensional Preference Analysis, and Exploration of Associated Imagination on Sound Perception (AISP). This paper gives a short overview of the OBELICS project results and improvements made during the last five years in associated engineering tools and methods for vehicle product sound design.