Sound imaging method and apparatus
US5105462A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1991 |
| Grant date | Apr 14, 1992 |
| Priority date | — |
| Expiry date | May 2, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04S2420/03
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The illusion of distinct sound sources distributed throughout the three-dimensional space containing the listener is possible using only conventional stereo playback equipment by processing monaural sound signals prior to playback on two spaced-apart transducers. A plurality of such processed signals corresponding to different sound source positions may be mixed using conventional techniques without disturbing the positions of the individual images. Although two loudspeakers are required the sound produced is not conventional stereo, however, each channel of a left/right stereo signal can be separately processed according to the invention and then combined for playback. The sound processing involves dividing each monaural or single channel signal into two signals and then adjusting the differential phase and amplitude of the two channel signals on a frequency dependent basis in accordance with an empirically derived transfer function that has a specific phase and amplitude adjustment for each predetermined frequency interval over the audio spectrum. Each transfer function is empirically derived to relate to a different sound source location and by providing a number of different tr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.