Pascal Broccolichi    The measurement of sound

Christophe Kihm

I first met Pascal Broccolichi in the context of his exhibition at capc. Before we got down to concrete discussions he switched on his laptop, and we looked at a 3-D simulation of the installation he was planning for the museum. This type of presentation is no longer exceptional – digital techniques for modelling volumes, plans and maquettes are ever more user-friendly and readily available. But in the framework of this particular project, it seemed to me that such techniques, and their graphic components, had taken on a wholly different status. More than just handy tools, they were an important part of the artist's approach. With his simulations we were already at work, and already in the sound work – in a sequence of operations that would turn a proposal into a finished form.
What was to be seen in these images of spaces modelled in three dimensions ? A route through Capc, as dictated by Broccolichi's installation Dial-O-Map 25°, and showing it in two different modalities: viewed from the ground level walkways, and from a gallery higher up. Looked at from ground level, the installation took the form of a large "arena" which occupied most of the available floor space. The visitor was allowed to move round the perimeter, but the setup in the centre was not physically or visually accessible. The enclosure was structured by acoustic screens at a height of 3.04 metres, totally closed in on themselves. The view from the gallery, on the other hand, made it possible to see the sound setup at the centre of the "arena", with its three audio modules, each comprised of four loudspeakers, two amplifiers, two reflectors and a subwoofer. These modules were lined up in the middle of the space, the subwoofers being placed along the central axis of the columns. Equipped with reflectors, they stood out symmetrically according to a stereophonic schema on either side of this axis. The installation thus allowed for two differentiated ways of looking at the exhibition space, with forbidden visibility being set against permitted visibility. What both these modalities did, in the first place, was to distance the listener from the sound-emitting setup, while revealing some of its technical characteristics. All the elements, from the acoustic screens to the subwoofers, were perfectly visible as such; and it would really be more accurate to describe the installation as an unadorned setup that the artist had formalised in a specific way – arbitrarily, with regard to the choice of white for all its components, objectively taking into account spatial demands in their alignment, height, width and angle of inclination – without trying to mask either their physical characteristics or their auditory functions. As for the distance to be maintained between the listener and the sound setup, Broccolichi was clearly playing with a definition of "listening", which, in the path round the installation, its relationship with the building and the resulting constant distance, resulted in two different mixing possibilities. The first was actualised by the listener himself, according to his position in the exhibition space. He had no influence at all over the sound level, and very little over its intensity (unlike the concert-goer, who can choose his distance from the sound source). But the mix of sounds that he heard would continually change according to his position in the space and that of the three audio modules, given the linear axis of their arrangement on the two sides of the gallery. The co-extension of this mixing to the movements of the listener-spectator would make the latter a sort of "sound surveyor". And this approach, which had already been used by Broccolichi in other works, also involved a grid pattern that governed the sound recording process. The second mixing possibility was to be actualised by the sound emission system. The three audio modules were differentiated, like three separate tracks, but their simultaneous presence in place and time allowed their output to be mixed. And extreme sensitivity to variations in volume meant that the reverberation of the building could be treated differently to its resonance. It was thus the activation of the programme, and its actualisation by the listener, that would give rise to individual auditory experiences.
The initial impression, which resulted from the difference between visualisation at ground level and from the gallery as a de facto separation between two separate aesthetic experiences, was thus contradicted by the logic of construction of the sound installation, as determined by functional and technical constraints. These visual games of masking and unmasking, relative to the listener's position in space, had to be seen as effects of the sound setup, with the overall structure and design of the installation being viewed as a functional architectural complex – that of a huge machine for sound production, intended specifically for an exhibition space whose acoustic properties determined the machine's dimensions.
A description of this in situ work therefore requires two terms: "architecture" and "installation". These are somewhat overused, having long been applied indiscriminately to all sorts of artistic object, the only condition being the denotation of a space and a sound (sounds in spaces, sound systems, sound works, etc.). But in this particular case they were fully applicable to the installation, given the artist's intention to utilise the physical properties of the site, and the auditory architecture, with an acoustic analysis that allowed the characteristics of the site to be optimally exploited.
In this sense, Broccolichi's work was to be like a dialogue. He first produced a sound map, then an auditory redeployment of the place itself in space. But one has to beware of flawed interpretations, because although the last two terms of the Dial-O-Map 25° sequence specified, on the one hand, the listening angle of the listener-spectator's position with regard to the gallery (25°), and on the other hand the topographical perspective derived from the pre-established grid pattern (which served, as we shall see, to work out a sound spectrum), the "Dial" term did not, strictly speaking, suggest a dialogue, in that it referred to a radio transmission mode – short-wave reception, to be exact.
In this respect there was no dialogue with the site itself, other than in the recording and (re)transmission of sounds produced in and by its architecture, and thus a dialogical relationship of resonances and responses, rather than a dialogue in the linguistic sense of the word. But one further characteristic of the project ought to be noted. Broccolichi rounded out its dialogical aspect, and showed how it hung together with the concept of "sound architecture" – that of the auditory material itself. All the sounds needed for Dial-O-Map 25° were recorded by him over a two-year period, using ultra-low-frequency antenna-receivers and seismic sensors to draw up an "inventory of disturbances in the electrical grid and vibratory movements in the different parts of the building". This was a scientific analysis, not just of auditory and acoustic parameters but also of the "residual sounds" produced by the electrical structure of the architectural structure. Indeed it was the exploration of this invisible electrical system deep within the edifice itself that provided the installation with its raw material.