  Goniometers, also known as Phase Scopes or Vector Scopes, are audio metering
tools that help music producers and mixing engineers monitor spatial aspects of
a music mix, such as the stereo panorama, the width of single sources, the
amount and diffuseness of reverberation as well as phase cancellations that may
occur on the sweet-spot and in a mono-mixdown. In addition, they implicitly
inform about the dynamics of the sound. Self-organizing maps trained with a
goniometer, are consulted to explore the usefulness of this acoustic feature
for music information retrieval tasks. One can see that goniometers are able to
classify different genres and cluster a single album. The advantage of
goniometers is the causality: Music producers and mixing engineers consciously
consult goniometers to reach their desired sound, which is not the case for
other acoustic features, from Zero-Crossing Rate to Mel-Frequency Cepstral
Coefficients.
