Wave field synthesis

Wave field synthesis (WFS) is a spatial audio rendering technique, characterized by creation of virtual acoustic environments.

It produces artificial wavefronts synthesized by a large number of individually driven loudspeakers from elementary waves.

WFS is based on the Huygens–Fresnel principle, which states that any wavefront can be regarded as a superposition of spherical elementary waves.

In practice, a computer controls a large array of individual loudspeakers and actuates each one exactly by the time and level at which the desired virtual wavefront would pass through its point.

For reproduction, the entire surface of the volume would have to be covered with closely spaced loudspeakers, each individually driven with its own signal.

Moreover, the listening area would have to be anechoic, in order to avoid sound reflections that would violate source-free volume assumption.

But already with that restriction the Listeners at wave field synthesis are no longer relegated to a sweet spot area within the room.

This reduces the influence of the listener position because the relative changes in angles and levels are clearly smaller compared to conventional loudspeakers located within the rendition area.

There are undesirable spatial aliasing distortions caused by position-dependent narrow-band break-downs in the frequency response within the rendition range.

For virtual acoustic sources placed in front of the loudspeaker arrangement, this pressure change hurries ahead of the actual wavefront whereby it becomes clearly audible.

[citation needed] Further work was carried out from January 2001 to June 2003 in the context of the CARROUSO project by the European Union which included ten institutes.

[citation needed] The WFS sound system IOSONO was developed by the Fraunhofer Institute for digital media technology (IDMT) by the Technische Universität Ilmenau in 2004.

The first live WFS transmission took place in July 2008, recreating an organ recital at Cologne Cathedral in lecture hall 104 of Technische Universität Berlin.

The startup eschewed the usual restriction to a horizontal plane and installed 96 individually controlled speaker drivers in a modular system.