Headphone Stereo Enhancement Using Equalized Binaural Responses To Preserve Headphone Sound Quality

A criterion is described and evaluated for equalizing the output of binaural stereo rendering networks in order to preserve the sound quality of the headphone. The aim is to equalize the binaural filter so that the sum of the direct and crosstalk paths from loudspeakers to each ear have flat magnitude responses. This equalization criterion is evaluated using a listening test where several binaural filter designs were used. The results show that preserving the differences between the direct and crosstalk paths of a binaural filter is necessary for maintaining the spatial quality of binaural rendering and that post equalization of the binaural filter can preserve the original sound quality of the headphone. Furthermore, post equalization of measured binaural responses was found to better fulfill the expectations of the test participants for virtual presentation of stereo reproduction from loudspeakers.