THE INTERMEDIATE AND ABSTRACT REPRESENTATION OF SPACE AS A TOOL FOR SOUND SPATIALIZATION ; LA REPRÉSENTATION INTERMÉDIAIRE ET ABSTRAITE DE L’ESPACE COMME OUTIL DE SPATIALISATION DU SON ; THE INTERMEDIATE AND ABSTRACT REPRESENTATION OF SPACE AS A TOOL FOR SOUND SPATIALIZATION: Challenges and consequences of the musical appropriation of Ambisonics and of experiments in the spherical harmonics domain. ; LA REPRÉSENTATION INTERMÉDIAIRE ET ABSTRAITE DE L’ESPACE COMME OUTIL DE SPATIALISATION DU SON: Enjeux et conséquences de l’appropriation musicale de l’ambisonie et des expérimentations dans le domaine des harmoniques sphériques

The creation of sound effects in space with Ambisonics highlights the musical potential of sound field decomposition by spherical harmonics, and redefines the representation of the sound space. This thesis defends that the abstract and intermediate representations of the sound space make it possible to develop new original approaches to sound spatialization. The reasoning that leads to this affirmation begins with the musical appropriation of the ambisonic approach. The creation of new space and sound processing patterns in Ambisonics leads to an original way of using signals associated with spherical harmonics, and to a different conception of the relations between them, and their hierarchization. The specificities of these experimental approaches and the singular characteristics of the sound fields generated call for the design of new theoretical and practical tools, for their analysis and restitution. The performed changes make it possible to free this approach from the initial technical and material issues of Ambisonics. But above all, it emancipates this approach from the psychoacoustic and acoustic models on which ambisonic techniques are originally defined. In this context, the signals associated with spherical harmonics are no longer necessarily a rational representation of the sound field but become an abstract representation of the sound space possessing in itself a musical potential. To validate the hypotheses, this thesis then proposes a new spatialization model based on a matrix decomposition of the sound space. ; Penser les traitements du son spatialisés en ambisonie permet de mettre en valeur le potentiel musical de la décomposition du champ sonore en harmoniques sphériques, et amène à redéfinir la représentation de l’espace sonore. Cette thèse défend que les représentations abstraites et intermédiaires de l’espace sonore permettent d’élaborer de nouvelles approches originales de la mise en espace du son. Le raisonnement amenant à cette affirmation commence par l’appropriation musicale de ...