[helmut oellers]

Caruso was a mono sound source without all doubt. Therefore seems
sufficient the transfer of the assigned pure audio information in a
single mono channel. The spatial sound field becomes created in the
Milan Scala only by the fact that a large number of spatial dispersed
mirror sound sources occur. According her room positions arise signal
delays regarding the listener and the reflection factors by the
surfaces influencing the frequency response and level of these mirror
sound sources. Though the signal itself always is Caruso's mono
source.
The conventional methods are now seeking to reduce the spatial
distribution of those sound sources upon few audio channels by
psychoacoustic principles. This always caused a loss of spatial
information. Much more effective seems the synthesis by the rendition
side, by which in principle all sound sources in their correct
position can be mapped.
This " Wave Field Synthesis" approach is known since two decades,
depicted by

http://en.wikipedia.org/wiki/Wave_field_synthesis.

Let´s discus the advantages and disandvantages of this approach.

Regards Helmut
www.syntheticwave.de