on the localisation in the superimposed soundfield - Hauptmikrofon ...

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occurrence of laterally displaced auditory events. Nevertheless, there is no
verified hypothesis that allows for a generalisation of these findings with respect
to spatial hearing. Hitherto, the functional relationship between lateralised
and localised auditory event locations is unknown (see Chapter 5).
4. The “cocktail party effect” implies that a target signal arriving from a certain
direction will be masked less by an interfering signal arriving from a different
direction if a subject listens binaurally rather than monaurally. Generally
speaking, for both the superimposed sound field as well as headphone-based
sound reproduction, the masking threshold for the target signal decreases if the
target and masker signals produce auditory events at different locations. It
seems that lateralisation experiments conducted in the area of binaural signal
detection are clearly related to the question of which ear signal components
can be discriminated by the hearing system in the superimposed sound field.
Up to now, however, little is known about the significance of so-called “detection
models” to the localisation process in the superimposed sound field (see
Section 4.3.2).
These examples indicate that rather than investigating it “holistically”, the spatial
hearing mechanism of the auditory system has largely been studied in terms of
demarcated sub-areas so far. Perhaps this may be explained by the efforts of
communications engineers to model immediately any observed relationships between
properties of sound and auditory events in the form of psychoacoustic principles,
thereby necessitating a precise demarcation.
The above examples further show that especially the limits of the areas of validity of
individual auditory phenomena as well as possible interrelations between these
phenomena must be of particular interest, which can also be said about the findings
from other scientific fields such as neurophysiology and perceptual research. In this
respect, the use of associative storage technology, signal processing (e.g. see
WIGSTROEM 1974, WILLWACHER 1976, KOHONEN 1977, BOHN 1978) and
possibly also holography (see WESS / ROEDER 1977) may create new possibilities
(see Section 3.2.1).
In this thesis, a model for the localisation process in the superimposed sound field will
be described that takes into account a large number of different auditory phenomena
in a uniform manner. It is based on the notion that localisation occurs due to a
“comparison of current and learnt stimulus patterns” (PLENGE 1973). That is, the
mapping of auditory events takes place as a result of auditory experience. If the ear
signals’ dependency onto sound source location is interpreted as a mechanism for
encoding spatial information, then knowledge of this dependency can be seen as a key
for decoding the spatial information. In the superimposed sound field, localisation
therefore manifests itself as a process for the simultaneous decoding of different