Virtual sources represent physical objects that emit sound into space. They are made of one or more (stereo, multichannel) audio source(s), and can be freely positioned around the audience. Those sources include an acoustic simulation module (with reverberation), that can be automatically controlled by the position of the source.
Mono sources are virtual sources. They can be positioned anywhere around the audience.
Stereo sources are virtual sources composed of two mono sources, their spacing is set by the . The position of a stereo object is set by its center and its .
Multichannel sources are virtual sources that are composed of multiple mono sources. Their layout can be manually adjusted, but will correspond by default to ITU standards.