SOURCE - A Stereophonic System for Engine and Vehicle Sound Recordings

The subjectively perceived playback quality of conventional artificial head recordings does not fully comply with the original perception of engine and vehicle interior sound. There exist differences in subjective perception between different artificial heads and even between models of one supplier. Additionally, the listening situations are often judged unnatural. One important reason for these problems is the fact that the transfer function of an artificial head system is always different from the torso and the outer ear transfer function of a specific person. The neurological processing of a specific test person is not trained to the significantly different head related transfer functions of the conventional artificial heads. Especially the significant differences of the outer ear transfer functions between an artificial head and a specific test person are considered as a main reason for an unnatural playback quality.

Starting from concepts of stereophonic recording systems which are the standard in the audio industry, this paper describes the development and the acoustic performance of a methodology we have named SOURCE in comparison to conventional artificial head systems. Besides a short description of the artificial head recording technology in comparison to the approach with SOURCE, benchmarking data and justifications for the superior performance of SOURCE recordings are given.