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hearing: 1: to perceive or apprehend by the ear; [...] 1: to have the capacity of apprehending sound; [...] 1: the process, function, or power of perceiving sound; specif: the special sense by which noises and tones are received as stimuli; [...] [217]

The main attributes used for describing a hearing event are:

is the auditory attribute on the basis of which tones may be ordered on a musical scale. Two aspects of the notion pitch can be distinguished in music: one related to the frequency (or fundamental frequency) of a sound which is called pitch height, and the other related to its place in a musical scale which is called pitch chroma. Pitch heights vary directly with frequency over the range of audible frequencies. This 'dimension' of pitch corresponds to the sensation of 'high' and 'low'. Pitch chroma, on the other hand, embodies the perceptual phenomenon of octave equivalence, by which two sounds separated by an octave (and thus relatively distant in terms of pitch height) are nonetheless perceived as being somehow equivalent. This equivalence is demonstrated by the fact that almost all scale systems in the world in which the notes are named give the same names to notes that are roughly separated by an octave. Thus pitch chroma is organized in a circular fashion, with an octave-equivalent pitches considered to have the same chroma. Chroma perception is limited to the frequency range of musical pitch (50-4000 Hz) [218].
is the subjective intensity of a sound. Loudness depends mainly on five stimulus variables: intensity, spectral content, time, background, and spatial distribution of sound sources (binaural loudness) [296].
also referred to as sound quality or sound color. The classic negative definition of timbre is: the perceptual attribute of sound that allows a listener to distinguish among sounds that are otherwise equivalent to pitch, loudness, and subjective duration. Contemporary research has begun to decompose this attribute into several perceptual dimensions of a temporal, spectral and spectro-temporal nature [218].
Spatial attributes
of a hearing event may be divided into distance and direction:

The perception of a direction of a sound source depends on the differences in the signals between the two ears ( interaural cues: interaural level difference (ILD) and interaural time difference (ITD)) and the spectral shape of the signal at each ear ( monaural cues). Interaural and monaural cues are produced by reflections, diffractionsa and damping caused by the body, head, and pinna. The transfer function from a position in space to a position in the ear canal is called head-related transfer function (HRTF). The perception of distance is influenced by changes in the timbre and distance dependencies in the HRTF. In echoic environments the time delay and directions of direct sound and reflections affect the perceived distance.

next up previous contents
Next: Somatic senses Up: Human Input Channels Previous: Vision

Esprit Project 8579/MIAMI (Schomaker et al., '95)
Thu May 18 16:00:17 MET DST 1995