Progressing from this basic assumption, Schaeffer investigated the en­counter between sound and image and denied the pre-eminence invariably accorded to synchronization in most theories of audiovisual communication. He was convinced that synchronization is to be treated not as a problem of meanings that are more or less in agreement (consonance and dissonance) but rather as an opportunity to organize sensorial stimuli of varying impact in their temporal succession. In this context he used a metaphor borrowed from acoustic physics, describing audiovisual synthesis as a phenomenon of mask­ing. Just as the overlay of two audio events can give rise to quite differ­ent acoustic sensations (ranging from the clear perception of two distinct entities to their fusion in a single object), so sounds and images are able to cover up one another, to be perceived simultaneously as distinct, to blend into complex elements, or again to generate sensations quite extraneous to the mere coinci­dence of the stimuli. Of particular interest is the difference he made between ‘synchronism’ and ‘syntony’: in the first case a perfect rhyth­mic adherence between what one sees and what one hears generates a “[…] particularly acute sensorial emotion, euphoric and more often than not comic” (Schaeffer, 1946c: 53). Audio comments that slavishly accompany a sequence of images only rarely have any real dramatic efficacy, whereas when different rhythms are juxtaposed “[…] impressions of the same audi­tory and visual force react with each other to create a sensation that can usefully be compared to the differen­tial and additional sounds in acoustics” (ibidem). Striking images and music, for example, intervene incisively in the temporal experience of the perceiving subject, organizing it in a contrary and complementary manner as an authentic ‘counterpoint’ of sounds and images. For Schaeffer this expression is by no means merely metaphorical, for it ex­presses that principle of the complemen­tarity of events which occurs in music when independent melodic lines overlap. It is perhaps appropriate to recall that it is precisely on this point that the theoretical approaches pur­sued by Schaeffer and the pupil of his who did most work in the audiovisual domain, Michel Chion, are most at odds. The younger scholar took issue with the metaphor of counterpoint, claiming that in the cinema “[…] harmonic and vertical relations (whether they be consonant, dissonant, or neither, à la Debussy) are generally more salient — i.e., the rela­tions between a given sound and what is happening at that moment in the image” (Chion, [1990] 1994: 36). This contradiction is in fact not based on a matter of principle but rather on different aesthetic viewpoints: Chion gave more importance to the narrative aspect of cinema (what happens on screen), while Schaeffer was interested in formal architecture and gave little or no thought to the narra­tive. For him noises, voices and music are elements of the audio discourse, distributed over time according to a syntactic logic which cannot ignore the visual objects projected by the film. Nonetheless the divide becomes more significant in syntactic and semantic terms, for Chion does not recognise a single entity called ‘sound track’, while Schaeffer argued that the continuity of sound has to be organized like a musical score, with careful management of analogies and differences, densities and stratifications, accelerations, re­prises, variations and cadences. Here one sees all the original­ity of Schaeffer’s approach, for, unlike many studies conducted at the time or in­deed since, he attributed a decisive importance to forms of composition that experimented with the audiovisual texture, partially freed from the obliga­tions imposed by film narration and hence more receptive to solutions prompted by principles of free formal organization.

Le contrepoint du son et de l’image (Schaeffer 1960) was the title of a later essay, published nearly 15 years after the texts we have been discussing. In this essay he considered the correlation between the visual and acoustic dimen­sions, starting from a description of the psycho-physiological processes of perception. Images and sounds have in common the same me­chanism of ex­citation of the sensory organs by vibratory phenomena organized in scales of frequencies. By interpreting these solicitations the in­dividual can recognise the outlines of objects that persist over time, according to analogous modalities of onset and extinction. The duration of the objects is thus the second level of correlation between the two sensorial fields, and in this case too can manifest itself either in terms of perfect adhe­rence or as total disorganization. Schaeffer gives the example of a soap bubble juxtaposed with a note struck on the piano: both images emerge from nothing and evolve over time, but have different modalities of extinction: sudden in the case of the bubble, gradual for the note. On the basis of this type of consideration it is possible to organize  a whole network of relation­ships between objects so as to create more or less complex film textures. The objects of representation in turn can be organized in more extensive se­quences endowed with autonomous rhythmic progressions. This brings us back to the concept of counterpoint, whose interest lies more in the stratifi­cation of the impulses than in a perfect vertical overlay.

Viewed as a whole, even taking into account only the few elements I have been able to cover, Schaeffer’s theory is seen to have both an epistemo­logical and a poetic orientation. In fact the deciphering of audiovisual mechanisms always generates opportunities for proposing practical insights which can be immediately put to good use in the creation of new works. When placed in the context of the creative experience of this composer and theoretician, this latter consideration prompts us to investigate the fruitful activity of audiovisual production he undertook and promoted from the in­ception of the Groupe de Recherche de Musique Concrète (founded in 1951). Much remains to be done, but in view of the quantity of documents available and the originality of the aesthetic premises they represent, this investigation promises to produce particularly significant results for the extension and development of a modern theory of audiovisuals.