If we reproduce Kunstopf recording using loudspeakers, the required separation of the right / left channels is insufficient. This cross-talk is intensified when loudspeakers stand close together, as in televison sets. Cross-talk cancellation must be used to separate the two stereo channals more effectively. Here the left signal cross-talk to the right ear is eleminated.
This is accomplished by post-editing the original signal where the cross-talking signal is deleted by an out-of-phase clearing signal. This clearing signal on its part effects a cross-talking to the left ear. This is compensated by an additional signal which effects a cross-talk to the other ear again. After five degrees of compensation the remaining cross-talk signal is no longer audible.
The idea for this method was developed in the sixties but an acceptable solution of appropriate quality was only feasible with the availability of modern digital signal processing technology. This method is applicable for all stereophone procedures and might also be used to substitute complex and expensive Surround Sound systems. Currently the "Institut für Technische Akustik der RWTH Aachen" and other scientific groups worldwide, are developing further advances on this technology.