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

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phenomena of spatial hearing, hence offering new possibilities for their explanation.
Initially, this approach appears functional for two reasons:
1. It can offer an explanation for the ineffectiveness of the comb filter effect in
the phantom source situation (see Section 3.2.2).
2. It agrees with the hypothesis that localisation should be seen as the consequence
of a perceptual process, which arises due to auditory experience
alone (see Sections 3.1.2 and 3.2.1).
Therefore, the new localisation model contains a processing stage that, as a result of
auditory experience, can separate such ear signal components. These components are
coupled to each other due to the effect of the head and pinnae in the superimposed
sound field. In the following, these ear signal components shall be described as
“localisation stimuli”.
Definition:
Sufficiently broadband ear signals or ear signal components at the ear drums of
the two ears together constitute a localisation stimulus if, based on their temporal
and spectral properties, they can be mapped to a single sound event location.
The processing stage for the selection of localisation stimuli is called “location
association stage”. It precedes a second, higher-level central processing stage
contained in the model. This so-called “gestalt association stage” comprises those
processes that determine the qualitative properties of an auditory event except for its
spatial characteristics (see Section 3.2 for details).
Hence, the localisation model is essentially characterised by two-dimensional
stimulus processing. The rigorous differentiation of the two processing stages
corresponds entirely to the two elementary areas of auditory experience: the received
ear signals can be attributed to the two sound source characteristics of “location” and
“signal”, which always occur in a pairwise fashion. As a result, the auditory events
occurring in the model can be traced back to the effects of a location- and gestaltdetermining
processing stage.
A stimulus has to pass both of these stages for it to lead to a perception. The two
processes thus always determine the properties of auditory events in a conjoint
fashion. Consequently, the gestalt-determining processing stage is an element of the
localisation model as well.