This article systemizes the types of musical improvisation according to various approaches to this phenomenon. It uses as the basis the classification by Ernst Ferand, which presently needs to be supplemented and clarified. It was stressed that the most general approach to the phenomenon of musical improvisation is its classification based on the layer principle (folklore, academic music, “third” layer). Within these layers, there are various forms of musical improvisation whose systemization is based on different principles, including: performer composition (collective or solo improvisation), process technology (full or partial improvisation), thematic orientation (improvisation theme in a broad and narrow context), etc. It was emphasized that classification of musical improvisation by types is manifested the most vividly when exemplified by jazz, which sums up the development of its principles and forms that shaped up in the previous eras in various regions of the world and have synthetized in the jazz language, which today reflects the interaction between such fundamental origins of musical thought as improvisation and composition. It was stated that the basic principles for classification of the types of musical improvisation include: 1) means of improvisation (voices; keyboard, string, wind and percussion instruments); 2) performer composition (solo or collective improvisation); 3) textural coordinates (vertical, horizontal, and melodic or harmonic improvisation, respectively); 4) performance technique (melodic ornaments, coloring, diminutiving, joining voices in the form of descant, organum, counterpoint); 5) scale of improvisation (absolute, relative; total, partial); 6) forms of improvisation: free, related; ornamental improvisation, variation, ostinato, improvisation on cantus firmus or another preset material (Ernst Ferand). It was stressed that as of today, the Ferand classification proposed back in 1938 needs to be supplemented by a number of new points, including: 1) improvisation of a mixed morphological type (music combined with dance and verbal text in two versions: a) invariable text and dance rhythm, b) a text and dance moves that are also improvised); 2) “pure” musical improvisation: vocal, instrumental, mixed (S. Maltsev). The collective form was the genetically initial form of improvisation, which included all components of syncretic action and functioned within the framework of cult ritual. Only later did the musical component per se grow separated (autonomous), becoming self-sufficient but retaining the key principle of dialogue that helps reproduce the “question-answer” system in any types of improvisation – a system that serves as the basis for creation of forms in the process of improvisation. Two more types of improvisation occur on this basis, differing from each other by communication type (Y. Lotman): 1) improvisation “for oneself” (internal type, characterized by reclusiveness and certain limitedness of information); 2) improvisation “for others” (external type, characterized by informational openness and variegation). It was emphasized that solo improvisation represents a special variety of musical improvisation, which beginning from the Late Renaissance era becomes dominating in the academic layer, distinguishable in the initial phase of its development for an improvising writing dualism (M. Saponov). The classification criterion of “composition” attains a new meaning in the system of professional music playing, to which improvisation also belongs. Its interpretation becomes dual and applies to the performance and textural components of improvisation, respectively. With regard to the former, two types occur in the collective form of improvisation: 1) improvisation by all participants (simultaneous or consecutive); 2)improvisation by a soloist against the background of invariable fixed accompaniment in other layers of music performance. The following types of improvisation occur in connection with the other – textural – interpretation of the term “composition”, which means inner logical principle of organization of musical fabric (T. Bershadska): 1) monodic, or monophonic (all cases of solo improvisation by voice or on melodic wind instruments); 2) heterophonic (collective improvisation based on interval duplications and variations of the main melody); 3) polyphonic (different-picture melodies in party voices of collective improvisation); 4) homophonic-harmonic (a combination of melodic and harmonic improvisations, typical for the playing on many-voiced harmonic instruments). It was emphasized that in the theory of musical improvisation, there is a special view at texture: on the one hand, it (like in a composition) “configures” (E. Nazaikinskyi) the musical fabric, and on the other hand, it is not a final representation thereof, i.e., it does not reach the value of Latin facio (“what has been done”). A work of improvisation is not an amorphous musical fabric; on the contrary, it contains its own textural organization, which, unlike a written composition, is distinguishable for the mobility and variability of possible textural solutions. The article’s concluding remarks state that classification of the types of musical improvisation in the aspect of its content and form must accommodate the following criteria: 1) performance type (voices, instruments, performance method, composition of participants, performance location); 2) texture type (real acoustic organization of musical space in terms of vertical, horizontal and depth parameters); 3) thematic (in the broad and narrow meanings of this notion: from improvisation on “idea theme” or “image theme” to variation improvisations on “text theme”, which could be represented by various acoustic structures: modes, ostinato figures of various types, melody themes like jazz evergreens, harmonic sequences, etc.).
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