The scientific problem of the dissertation is the semiological conceptualization of the problems of intertextuality and intermediality within instrumental chamber art and substantiation of the foundations of the concept and typology of musical intermediality. The metascientific nature of the theoretical and methodological foundations of the cultural semiological paradigm of modern art history, which is manifested in the desire for comprehensive knowledge of the ontology, phenomenology, and hermeneutics of artistic existence and is based on the principles of interdisciplinary understanding of culturological discourse in the XX century. The high theoretical and practical significance of the study of the instrumental chamber art of Ukraine at the late XX – early XXI centuries in the cultural semiological concept sphere of modern art history is proved. In the process of concretizing the concept of “media” and defining its point in the conceptual system of the humanities, in particular art history, it became clear that its application becomes possible to define any medium – sign system, code, or specific channel or environment, which possess functions of the formation, translation, interpretation, and exchange of semiotic information, in particular, between artistic and symbolic codes of different arts, as well as artistic and non-artistic sign systems. The dissertation presents the concept of intermedial connections in the instrumental chamber art for the first time, which includes the principles of medial synthesis, transposition, and synergy. The latter is distinguished based on the study of explicit and implicit, multisemiotic and monosemiotic, coordination and subordination ways of functioning in the semiotic space of the instrumental chamber compositions of unrelated sign codes and stylistics of artistic and non-artistic origin. Numerous interstylistic, intergenre, intertextual, inter-authorial, and interspecific connections were analyzed in terms of the study of the semiosis of composer’s creativity and the related poetics of the author’s artistic and musical consciousness. From the point of view of the semiology of music, they are actualized in the process of modeling instrumental chamber works on intra-semiotic (intramusical, intertextual) and intersemiotic (interspecies, intermedial) artistic-symbolic intersection of sign-symbolic codes and texts of culture, the semiotics, and semantics of the ones. The study of strategies of code-language and semantic modeling of works of the instrumental chamber art of Ukraine of the late XX – early XXI centuries reveals that actualized in ensemble music multilayered intertextual (auto intertextual) and intermedial connections form diachronic / synchronous set of explicit parallels. The mentioned parallels become a determining factor in activating the macrodialogue of cultures within the hypertext space of communication of linguistic and symbolic codes, cultural and artistic phenomena, and creative personalities of different cultural, historical, and stylistic epochs, countries, regions, art schools, and non-artistic practices. Determining the main trends in genre creation in the domestic technical and compositional practice of ensemble music of the late XX – early XXI centuries allows us to state that the intertextual and intermedial cultural and ideological content of musical aesthetics acquires crucial semiotic and conceptual meaning in the mechanisms of modern language and speech as well as genre formation in terms of the ensemble music. A question of reaching a new level of performing-interpretive universalism both in interstylistic and inter-artistic dimensions of ensemble creativity, characterized by the synergy of technical-performing, semiotic-communicative modes of various kinds: conventional / unconventional, manual / non-manual, musical / extramusical (in particular, verbal-vocal, paralinguistic, kinesics, etc.) is raised within the process of substantiation of the aesthetic-hermeneutic concept of modern ensemble performance. The mentioned polymodal vectors of ensemble vocabulary in the situation of their performance are always accompanied by the search for “mixed” interpretive schemes of acquisition, differentiation, and translation of the artistic expression meaning. The high potential of self-organization of Ukrainian ensemble members in generating large-scale concert-festival projects is noted within the process of characterizing the performing intermedial projects of Ukrainian ensemble members in the light of the director’s ensemble interpretation. They present integral semiotic complexes in the combined action of music, painting, video art, ballet-plastic, various video projections, light-visual, and object installations. The particular issue leads to the creation of new cultural contexts and intensifies interstylistic and cross-branch dialogue in the intertextual, intermedial, interactional space of the new system of artistic communication.