Wave field synthesis (WFS) is a spatial audio rendering technique, characterized by creation of virtual acoustic environments. It produces "artificial" wave fronts synthesized by a large number of individually driven speakers. Such wave fronts seem to originate from a virtual starting point, the virtual source or notional source. Contrary to traditional spatialization techniques such as stereo or surround sound, the localization of virtual sources in WFS does not depend on or change with the listener’s position.
By means of level and time information stored in the impulse response of the recording room or derived from a model-based mirror-source approach, a sound field with very stable position of the acoustic sources can be established by wave field synthesis. In principle, it would be possible to establish a virtual copy of a genuine sound field indistinguishable from the real sound. Changes of the listener position in the rendition area would produce the same impression as an appropriate change of location in the recording room. Listeners are no longer relegated to a "sweet spot" area within the room. 

The Moving Picture Expert Group standardized the object-oriented transmission standard MPEG-4 which allows a separate transmission of content (dry recorded audio signal) and form (the impulse response or the acoustic model). Each virtual acoustic source needs its own (mono) audio channel. The spatial sound field in the recording room consists of the direct wave of the acoustic source and a spatially distributed pattern of mirror acoustic sources caused by the reflections by the recording room surfaces. Reducing that spatial mirror source distribution onto a few transmitting channels causes a significant loss of spatial information. Much more accurately this spatial distribution can be synthesized by the rendition side. 

Concerning the conventional channel-orientated rendition procedures, WFS provides a clear advantage: "Virtual panning spots" called virtual acoustic sources guided by the signal content of the associated channels can be positioned far beyond the material rendition area. That reduces the influence of the listener position because the relative changes in angles and levels are clearly smaller as with closely fixed material loudspeaker boxes. This extends the sweet spot considerably; it can now nearly cover the entire rendition area. The procedure of the wave field synthesis thus is not only compatible, it clearly improves the reproduction for the conventional transmission methods.
Early development of WFS was started in from 1988 by the Delft University. Further work was carried out in the context of the CARROUSO project, promoted by the European Union (January 2001 to June 2003). In Europe, ten institutes were included in this research. The WFS sound system was developed by the Fraunhofer Institute for digital media technology (IDMT) by the technical University of Ilmenau. 

Loudspeaker arrays implementing WFS have been installed in some cinemas and theatres and in public range with good success. The first live WFS transmission took place in July 2008, recreating an organ recital at Cologne cathedral in lecture hall 104 of the Technical University of BerlinThe room contains the world’s largest speaker system with 2700 loudspeakers on 832 independent channels. 

Development of home-audio application of WFS has only recently begun.In spite of the efforts, large acceptance problems remain.

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