(40) L'espace composé dans l'acousmatique stéréophonique
(45) Analyser l’espace composé dans l’acousmatique stéréophonique
(46) L’espace composé dans l’acousmatique stéréophonique concerne les spectres sonores, façonnés dans l’espace vertical bidimensionnel et répartis dans un espace tridimensionnel généré par le champ stéréophonique du studio.
Composed space in the stereo acousmatic idiom concerns sound spectra, which are moulded in vertical, bi-dimensional, space and are mapped onto implied three-dimensional space within a stereo field in the studio. (46) The vertical and three-dimensional spatial dimensions of sound spectra comprise the sounding flow of the acousmatic work. Although indissolubly bound, spectral, vertical space and its deployment in three-dimensional space are separated for discursive purposes.
(47) Mon analyse et ma réflexion sur l’espace stéréophonique composé se concentre sur une courte section de Chat Noir. La section est représentée sous forme d’un exemple sonore et d’un système de transcription à deux niveaux. Le premier niveau comprend une série d’images stéréophoniques spatiales illustrant l’incarnation et le mouvement du flux sonore dans l’espace tridimensionnel selon des intervalles de deux ou trois secondes. Le second niveau analyse l’occupation verticale bidimensionnelle de l’espace spectral au cours du temps.
My analysis and discussion of composed stereo space centres on a brief section of Chat Noir. I would like to suggest a bifurcated approach to the analysis that, to my knowledge, has not yet been applied to this type of music. The discussion may appear technical, but the approach aims to inspire further research in this direction. The section of Chat Noir is represented by a sound example and a two-tiered scoring system. One tier examines the vertical, bi-dimensional occupancy of spectral space over time. (47) The way spectral space is filled and evolves is linked to the behaviour of the sounding flow in three-dimensional space and, consequently, the composer/listener’s perception of the sounding flow. The other tier comprises a series of stereo spatial images, illustrating the embodiment and movement of the sounding flow in a slice of three-dimensional space in two- and three-second intervals. This approach can be considered the aural equivalent of a series of time-lapse photographs taken of moving entities, and illustrates movement much the same way a photograph does of moving road traffic at night, where lights of cars appear to ‘stream’ in different directions, ‘tracing’ the movements of the cars in three-dimensional space.
(48) De manière à aider l’auditeur à passer d’un niveau à l’autre, les symboles alphanumériques associés à chaque son dans la légende de la transcription spectrale accompagnent la représentation du son dans les images stéréophoniques spatiales.
However, this bifurcated methodology is not without limitations, because when spectral space is illustrated over time, its three-dimensional behaviour is unaddressed. Conversely, a stereo spatial image, particularly one that is visually depicted from a vantage point directly above the listener, addresses the three-dimensional behaviour of the sounding flow in terms of proximity to the listener at the expense of the bi-dimensional subtleties and evolution of spectral space as it unfolds over time. In order to aid the reader to navigate between the two types of scores and vantage points, the alphanumeric symbol assigned to each sound in the legend for the spectral score accompanies the representation of the sound in the stereo spatial images. (48)
(49) Dans la figure 3 (voir 3.3.1), l’occupation de l’espace spectral dans Chat Noir (3’08”-3’14”) au cours du temps est illustrée telle qu’elle est établie par une écoute subjective. Les fréquences basses sont représentées en bas de la partition et les fréquences aigues en haut.
In Figure 3 (see 3.3.1), the occupancy of spectral space in Chat Noir is represented, from 3’08” to 3’14”, as established by subjective listening. Low frequencies are represented at the bottom of the score and higher frequencies at the top. (49) The left side of the figure contains a legend showing the categories of primary spectromorphologies found in this brief section. Different levels of opacity in the morphological design of sound spectra represent different levels of amplitude. For example, a transparent shade indicates a softer dynamic, and a more opaque shade indicates a louder dynamic.
(50) Les figures 4 à 6 (3.3.2), représentent l’espace tridimensionnel dans ce même extrait de Chat Noir, par référence à l’auditeur et à l’espace d’écoute.
In Figures 4-6 (see 3.3.2), three-dimensional space in Chat Noir is represented, from 3’08” to 3’14”, with reference to the listener and listening space. (50) The spatial images are scored in a time-lapse fashion, which permits the directionality, occupancy and behaviour of the sounding flow’s three-dimensional space to be viewed over brief intervals of time.
The listening space, which serves as a model for Figures 4-6, contains a sound playback system with two high-quality studio monitors. The triangular proportions, intuitively established between the left and right loudspeakers and the listener, were confirmed by Smalley, who had proposed a similar type of listening vantage point with a 1:1 ratio between the distance between the left and right loudspeakers and the distance from the centre of the loudspeaker image to the listener, one of a narrow range of position possibilities that offers suitable conditions for compositional and listening awareness (Smalley, 2007: 50).