Didactic Potential of Instructive Etude and its Explication in the Process of Professional Development of a Pianist

The article proposes an analytical approach to instructive etude as a musical work whose originality is determined by its functional orientation: not to demonstrate performing skills in mastering all its components or to embody author’s reflection, but to develop and improve students' practical skills. The creation of etude forming piano music in its sense in the aggregate of composing, performing, and teaching practices at their intersection allows us to see there a reflection of all the process facets stressing one of them. The instructive branch of the study, incorporating the finds of both performers and composers, projects them onto teaching materials, highlighting individual technical and textural techniques and turning them into the units of training work. The formation and improvement of the pianistic apparatus, the accuracy of touching the keyboard, free movement within its space boundaries, ease and fluency of fingers, etc., remain the most fundamental, basic task of instructional etude. However, the faultless technique and motility do not exhaust the content of the training work proposed by an etude’s author, but include other skills that also need careful work, including auditory control, the ability to withstand the taken tempo-rhythm, mastering various articulations, etc. The breadth and variety of methodological tasks posed in individual samples of instructive etudes are pointed out, which makes it possible to refer to them as a powerful aid in all stages of teaching music to students, including higher special musical institutions. Whether to use them in academic repertoire or abandon should depend only on a particular student’s professional level, and on his being ready to play compositions of increased difficulty, including artistic etudes. The conclusion is made about didactic potential steadiness inherited in this type of works and the tendency to explicate it in a pianist’s professional development process.


Introduction
The piano etude genre is inseparable from pianism as a special kind of artistic and aesthetic activity. Its emergence itself and crystallization into a certain type of composition took place in close interaction with other processes aimed at mastering a new instrument, playing tuition, and creating a specific piano repertoire. Thereby, there was a constant multi-vector results exchange of compositional and performing creative and pedagogical experience in musical historical practice, whose generalization can rightly be considered an etude. It is revealing that a significant contribution to this genre development was made by renowned composers: M. Clementi, F. Mendelssohn, R. Schumann, F. Chopin, F. Liszt, J. Brahms, C. Saint-Saëns, S. Rachmaninoff, A. Scriabin, C. Debussy, I. Stravinsky, B. Bartok, many of whom were no less great pianists. It is not surprising that the whole life of a performing musician from the first steps on the way to the doors of mastery to the very peak of creative achievements is unthinkable without referring to the etude genre. Taking an important place in pedagogical and further concert practice, the piano etude is a guarantor of the preservation and consolidation of the very foundations of pianism. Mastering them at different stages of professional tuition to play the instrument is impossible without systematic study of instructive etudes which are relatively small instrumental pieces, aimed at solving a certain methodological, first of all, technical (motility) task.
From the first months of piano training, easy etudes by A. Goedicke, H. Berens, L. Schytte, and then, over the years, more complex etudes by M. Clementi, C. Czerny, M. Moszkowski, and others become an important teaching material for teaching a young pianist. The need to master instructive etudes and their performance in educational practice is an indispensable condition for the formation and development and cannot be limited by technique skills of young musicians. Rhythmic and tempo stability, development of technical skill level in general, and musical form awareness are the positive result of qualitative "working-through" of such material. Obviously, when working with instructive etudes, one should also pay attention to intonational meaningfulness of a performance, careful listening to texture layers, variety and subtlety in dynamic gradations transmission and articulation, colorful piano sound. So, for example, E. Semenova notes: "Etudes and exercises perfectly "tone up" hands <...>. In addition to their own technical perfection, they are noticeably aimed at the formation of a pianist's sound culture" (Semenova, 2012, p. 128).
Unfortunately, many teachers underestimate the true role of instructive etudes in the process of teaching a pianist. Thus, in music colleges and even in specialized music schools, following the study plan as a basic "law letter", many young performers are "transferred" to the "high repertoire" of artistic studies too early, as a result, a young musician who has not yet reached the required level of pianistic training level falls into a state of constant stress. Instead of accumulating professional playing skills, he is plunged into the depths of "struggling" with musical material, which leads to the opposite result.
Therefore, a teacher's repertoire strategy calculated for individual capabilities of a particular student and the qualitative indicators of his growth as a musician is so important. Since artistic etudes most often represent the top of performing skills, sometimes surpassing long-form compositions complexity, the presence of these compositions in students' study plans should correspond to their level of pianistic training level.

Literature Review
Since piano etude is an important component of piano art, both practical and scientific interests are quite understandable, as evidenced by the multitude of devoted works. Some authors tend to consider piano etude in historical and theoretical aspects. For example, a number of studies research etudes of a certain historical period: the first half of the 19 th century (Terentyeva, 1974), the 19 th and 20 th centuries (Gultsova, 2018), the first half of the 20 th century (Grigorenko, 2013). The issues of the formation, genre evolution and its influence on 19 th century piano compositions became the study subject in the Master's thesis of V. Kozyr, a Kharkiv pianist (2008); "The semantic spectrum of the concept "etude", which corresponding to a large number of aesthetic meaning facets" is reflected in A. Genkin's article (2012, p. 132).
In most of the scientific works of pianists, teachers, and musicologists, the piano study is revealed in the context of the creative heritage of some composers like J. Hummel (Grokhotov, 1990), F. Chopin (Zenkin, 1997), F. Liszt (Milstein, 1961), etc. The etudes of a particular author are directly considered in the studies of M. Aranovsky (1963), M. Eshchenko (1973, D. Blagoy (1963). Recently, one can see the scientists (Genkin, , 2019, (Karpychev, 2018), (Kvasnikova, 2015) being interested in the figure of the outstanding pianist and teacher Carl Czerny, whose multifaceted activity has not received a proper assessment.
There is a strict hierarchical division among methodological works devoted to piano studies: the instructive repertoire for beginners plays a role of a material for methodological developments of children's music schools, artistic etudes are considered with regard to their high spiritual and aesthetic content. A publication by E. Semenova, addressed to the system of teaching in music performing classes of pedagogical universities should be considered as one of the exceptions, whose author analyzes the evolution of "the methodological views of the 19th century Western European piano school outstanding teachers specialized in improving the performance technique of pianists" (Semenova, 2012, p. 127). However, the problem of educating a music teacher in schools of general education, who are graduates of pedagogical universities, is researched based on artistic studies, although this piano repertoire can hardly be performed at the proper level by musicians who do not have a conservatoire education.
A clear preference is given to artistic etudes in modern programs of conservatoires. At the same time, instructive etudes are almost completely excluded, not being considered a necessary component of a pianist's education, and due to their "easiness" they are considered "unworthy" of the higher stage of musical education. Nevertheless, the piano repertoire, called instructive etudes, is not only very useful at the initial stage of the pedagogical process, but also extremely necessary in the subsequent stages of professional piano training.

Methods
The article uses research methods based on the general laws of didactics, the principles of training professional pianists, algorithm for performing analysis, as well as genre and typological approach in studying piano etude of different types.

Discussion
To begin with, we would like to recall one of R. Schumann's statements about etudes, which, in his opinion, "should teach something that you did not know how to do before" (Schumann, 1975, p. 8). In many of his articles, the composer dwells on this subject in detail, considering each piece of music as an etude. In the reviews of 1836, one can find his thoughts that no other piano music genre "can boast as many excellent works as an etude" (ibid.). According to R. Schumann, classes strengthening techniques should be skillfully combined with a pianist's musical sense development. This synthesis assumes a true role of the technical side in the performing process. "A beautiful thing is a complete virtuosity when it is a mean for transmitting genuine works of art" (Schumann, 1970, p. 251), the musician asserts in the letter to the composer and pianist C. Reinecke. This statement of R. Schumann reflects his views on the technical tasks of a performer, which, in his opinion, should always be subordinated to artistic goals.
It would seem that the validity of the above judgment does not raise doubts, however, the projection onto the teaching method of a performing musician still needs an explanation. It is about solving such an important task as the formation and mastering of the piano apparatus of any student, the development of strength and smoothness of playing the instrument, independence and fluency of fingers, which requires special attention, even at the cost of abstracting from the whole complex of skills. A special kind of etude helping to achieve these goals is intended for systematic work on the named basic component of piano performance.
There are symptomatic attempts to classify etudes in the entirety of available samples, constantly carried out by the genre researchers. N. Terentyeva (1974) proposes an etude typology, heuristic in its initial premises and the chosen criteria for differences. According to the author's characteristics, instructive etudes cannot be considered an artistic work of full value due to the lack of bright composer means. The melodic line, as a rule, is devoid of expressive intonation, has poor timbre, the harmonic plan is rather primitive, dynamic remarks are presented sparingly, and the designations of the image and pedals are generally absent as a rule (ibid, p. 10). Character etudes belong to the "varieties of lyrical piano miniatures. Works of this type are sketches of human emotional states or nature landscapes" (ibid). Concert and artistic etudes are "brilliant virtuoso pieces that have vivid articism and are sometimes distinguished by sophisticated technical difficulties," besides, according to the author's observation, "the intensive development of melody and various musical episodes juxtaposition often entailed an increase in the works' form and volume scales" (ibid, p. 9).
The intraspecific classification of instructive etudes and exercises proposed by A. Genkin is of particular interest. Based on analytical observations on the etudes collection, Op. 299 and Op. 740, as well as Op. 365 exercises the author distinguishes three types: conditionally "training type", where all student's attention is directed to mastering a separate, most often elementary technique; "clean type", aimed primarily at solving technical problems as such, but possessing the properties of compositional integrity. This type has elements of piece thanks to its expressive and figuratively meaningful directions, bright articulation, and dynamic gradations, the most complex texture requiring the coordination of various skills and an integrated approach to learning an etude and its execution. However, even in the latter case, the instructive and training function of the etude is preserved, not allowing it to go beyond its type (Genkin, 2019. Thus, there is practical task expansion and the reveal of instructive etude didactic potential in the transition from one type of etude to another. This does not mean an absolute one-wayness of a student's professional progress: from "exercise" to "piece" and particularly from the instructive etude to the artistic one since it may be necessary to refer to purely training exercises, the relevance of including etudes of any type into piano student repertoire remains as a result. The main thing is that the general methodic line of training should be maintained based on its progress principle and on the prohibition of setting complex tasks in the absence of confidence in solving simpler ones.
It should be noted that concentration on motility skills does not at all mean the rigid nature of play and self-sufficient movement energy. An aspiring pianist mastering the basics of piano technique should be aware that he not only learns to play the piano, but also studies music; in other words, even the easiest etude entrusted to him by a teacher is a product of intonation and sound construction, human reason, creative thought, activity experience, and it should be treated accordingly. This exact understanding not only of an instructive etude, but also of exercises was typical for C. Cerny: the thesis was purposefully proved in the aforementioned monographs by A. Genkin (2019. Focusing on instructive etude as a kind of musical composition expands its "training" possibilities, becoming an excellent material for forming a student's ability to study any new opus competently. In order to "hear the modal features and coloring and determine the location of fingers on white and black keys" (Pupina, 2012, p. 28), the student can be recommended to do one of the difficult and useful tasks that is transposing an etude or its fragment into other modes.
An equally important factor in performing analysis is rhythm, one of the most important expressive elements of music and methods of its organization. It will be appropriate to use the technique of intoned counting out loud bars by phrases in one breath. Complicating the process of working out the musical material, one can play on fingerboard with one hand, and on lid (or music desk) with the other one, whereby it is suggested to beat out the strong beat with the right foot, and the down one with the left foot. One should also pay great attention to maintaining the bass line, which contributes to logical forming of melodic lines. It is useful to learn bass line by heart, and to transmit each musical texture layer into performance alternately. Based on a carefully elaborated bass line, it is possible to complicate working on texture by building up a harmonic vertical structure, achieving a balance between voices, purity, and beauty of tone. Working on sound presupposes "pre-hearing" the desired result. The acoustic properties of the instrument make it possible to capture physical vibrations of resonating strings. A student must possess a certain skill in order to feel strings' vibration and transmit the generated sound into the next one. While practicing various texture formulas in an etude, one can exercise at a slow tempo and listen to the physical properties of the sound wave and go along with them very carefully.
Without a prominent melody line, one should first detect intonation points in rhythm figures and focus on them. It is necessary to focus students' attention on the strict implementation of dynamic shades in etudes, since they are connected with the figurative structure of a composition and often play a formative role. The correct performance of an author's articulation is obligatory, which enriches the musician's playing articulatory. The composition of a piece can be "assembled" by counting the number of measures aloud by melodic lines. Finally, it is recommended to use a blindfold play of etudes or their performance in the dark. This technique is especially effective to control mastering of technically rich, complex episodes. Using such techniques "promotes a better concentration of a pianist's attention, improves sense of pitch, preserve precise muscle movements, and reveals hidden technical hotspots" (Pоupina, 2012, p. 32).
It is very important to convince a student that solving problems of "technique material mastery" (Prikhodko, 1997, p. 49), finding means "minimizing texture difficulties, finding the most appropriate and effective play movements" (ibid), serve as the basis where "free" auditory control will be able to provide sound "contact" with the instrument. Concert and artistic etudes, often distinguished by an abundance of various texture elements implying a musician's readiness to perform them, are especially difficult in this regard. Consequently, a pianist must already be well-trained and professionally mature by the time of choosing a similar repertoire.
An instructive etude, as a rule, contains one playing formula that is a kind of pianism "puzzle"; thus, a student is first of all concentrated on its development. However, this case also implies auditory control and necessary coordination of movement with final sound and intonation, which ensures performance meaningfulness. What is more, according to A. Genkin's conclusion made on the basis of studying C. Czerny's methodological works, the outstanding teacher did not tire of reminding that "being abstract and at first glance indifferent to musical semantic side pianistic formula can generate a meaning beyond music, appealing to a feeling and imagination of any etude performer. There are always technique and aesthetically expressive principles" . According to the abovementioned researcher, the instructive and expressive meaning of Czerny's training materials is evidenced by "dynamic shades, indications of tempo and character, not to mention rhythmic and texture details, <...> any etude or exercise sample contains musical information, therefore, possessing aesthetic sense" (ibid).
It is no coincidence that various types of piano techniques are described in the scientific works by renowned pianists of the 20 th century, being the basis of the so-called "pianistic texture formulas". We will indicate only the most significant studies. So, H. Neuhaus names such various types of technique as "blanks", "raw materials", "semi-finished products" (1961, p. 38). He suggests breaking them down into elements: "playing one note" (ibid, p. 138), trill, scales, arpeggios, double notes (from seconds to octaves, and then to nonas and decimas) (ibid, p. 145), three-, four-, five-note chords, long hand skips (ibid, p. 160). S. Feinberg gives great importance to finger and octave technique, chord passages, double notes, complex vocalism (1969, p. 268), and also emphasizes their deep connection with style, sound, and artistic features of a work (ibid, p. 255). Ye. Lieberman also points to the unity of these factors, defining the type of technique as "playing movement helping a pianist to overcome specific texture difficulties in the simplest and most convenient way, while achieving the artistic and sound result he needs" (1985, p. 83). S. Savshinsky writes about the formulas of "pianistic movements mechanics" (1964, p. 108) and sees there elements of texture, noting, however, that all the technical elements necessary for a pianist are only the background "requiring additional work for artistic use" (ibid). A. Shchapov also considers pianistic techniques to be only means, the author "is primarily interested in the sound result of each technique <...> the sound is artistically expedient, dictated by a given work and episode" (1968, p. 8). The researcher describes numerous piano techniques, dividing them into three types: finger patterns, octaves, and chords. A. Birmak emphasizes that technique, first of all, is "an artistic component of performance, depending on content and style of a work," and gives his own classification of its types, based on "a subdivision based on musical texture techniques: finger play technique includes groups that cover no more than five notes without changing positions, scales and scale-like passages, arpeggios, double notes, trill, decorations (melismas), finger repetitions. Large-scale technique includes tremolo, octaves, chords and skips" (1973, p. 79). However, the author does not exhaust "the whole countless diversity of texture techniques" with such a classification (ibid).
The division into four groups of "fundamental formulas" of F. Liszt's pianism, given in the book of J. Milstein, is well known: octaves and chords, repetitions and trills, double notes (thirds, sixths), scales and arpeggios (Milstein, 1961, p. 185). The researcher not only names them, but also reveals the figurative and dramatic meaning of each one. For example, octaves and chords tend to be found at dramatically important climaxes that help create sound wideness. Combined with loud dynamics, they give the thematic material a solemn, elated, severe or victorious character filled with expression. Powerful loud chords that acoustically fill the sound space help to recover its multidimensionality. Quite often octaves and chords help to build melodic lines of themes. Chords apply to other dramatic purposes that sound within the piano gradation. They are used less often and appear depending on a certain figurative system.
Thus, music teachers and scientists are unanimous in their opinion about "finger fluency" is inseparable from the artistic, aesthetic, and semantic aspects of playing the piano, and ultimately from the whole complex of means inherent in musical art. This means that keeping the dominant training function in the instructive etude, it is necessary to remember not only about the motility, but also about other results of the ground work.
The interaction of motor and auditory components in the pianism of junior undergraduates is successfully improved while learning the well-known etudes by M. Clementi, С. Czerny, I. Kramer. Today, M. Clementi's etudes are known mainly from "29 Selected Etudes" collection edited by K. Tausig. Unfortunately, few are aware that these works are part of M. Clementi's fundamental threevolume edition of "Gradus ad Parnassum", whose full title sounds like this: "Step to Parnassus, or the Art of Playing the Piano, Embodied in Exercise in a Stern and Elegant Style" (Clementi, s. a.). This collection, served as a fundamental basis for pianistic skills education in the 19 th century, can be successfully used in teaching practice of secondary and higher educational institutions nowadays.
M. Clementi considered each of the exercises in "Gradus ad Parnassum" as an example or model, whose the purpose is to reveal a side in piano playing art to a performer. We should note that the term "exercise" should be understood not literally, but generalized (school, method). 100 exercises amaze with the variety of content and the volume of the assigned performing tasks. This is probably the reason for the genre diversity of the works included in this three-volume collection. Along with virtuoso pieces with continuous development based on elementary rhythmic and melodic formulas, the collection contains sonatas, scherzo, rondo, fugue, capriccio, as well as free-form pieces called "Adagio" and "Andante".
There are 29 etudes among the 100 exercises. Being parts of the collection's suites, they are necessary in the pieces collection. Practically they contain all possible types of performing techniques found in piano works of later eras.
One of the first examples of "typical" etudes in piano music can be considered etudes by I. Kramer. It is known that the outstanding English composer and pianist was one of M. Clementi's most talented students. His contemporaries enthusiastically noted his brilliant high-level piano playing skill. I. Kramer criticized thoughtless virtuosity and scorned the "piano acrobats" (Marmontel, 1885, p. 187). He was an extremely deep-looking musician who saw a sense in music. In addition to his own opuses, his concert performance programs included works by J. S. Bach, G. F. Handel, D. Scarlatti, M. Clementi. I. Kramer lived in England almost all his life and became famous for his concert and teaching activities. L. Beethoven referred to the musician's works; I. Moscheles and A. Henselt wrote the second piano part for I. Kramer's etudes. Practicing them with his students, A. Hanselt often accompanied the play of his students with his own improvisation on the second grand piano. A. Henselt recognized this authors' works as a law for every pianist: "I see the rebellious Moses with the Tablets before me," he said about Kramer's etudes" (V-va, 1914, p. 468).
The range of techniques used by I. Kramer in etudes is rich and diverse, which emphasizes the artistic side of his compositions. The collection "60 Selected Etudes" (edited by Bulov) contains techniques as necessary to create a certain figurative sphere. Using the example of the second and third notebooks (etudes XVI -XLV), we present the most typical piano techniques forming the basis of piano texture formulas in the outstanding English composer's work.
I. Kramer's etudes have a special energy, carrying memorable musical images, some of them express a certain emotional state, sometimes a vivid expression. This characteristic is facilitated by I. Kramer's etudes genre enrichment, as well as rather bright and artistically interesting intonation content. This approach leads to texture layers individualization; here, even techniques begin to function artistically, giving a certain sense to the general forms of piano movement.
Here are some examples: "specific texture formulas" (according to Lieberman) (XXI); an individualized figurative pattern woven into waltz texture (XXIII); melodious figuration enriched by grace notes technique (XXIV); sequences of ostinato figurations in the right hand in combination with counterpoint triplets in the left one, while articulation does not coincide (XXXII); harmonic figuration combined with remote bass (XLII); rhythmic figuration, alternately performed with both hands.
I. Kramer's large-scale technique is also represented quite widely: octaves (No. XXXII); chords (XLI); broken intervals (XIX, XX); arpeggio (XXVII); skips (XLV). I. Kramer uses polyphonic techniques to achieve a vivid image: a combination of differently articulated legato and staccato (XXV); counterpoint combinations of melodic voices (XXVII, XLIV). Polyphonization of texture is also observed in etudes with mixed technique types: a combination of polyphonic techniques in the right hand with harmonic figuration in the left one, while different articulation techniques are used simultaneously (XXII); there is a combination of double notes and grace notes technique (XXIX).
C. Czerny's etudes are the most popular ones in various national piano schools to this day. Being a teacher and a born mentor by nature and having an acute analytical mind, tending to structure of individual phenomena, the Austrian teacher left a huge heritage to his contemporaries and their descendants, numbering hundreds of musical and methodological works. The most ambitious of them is fully named: "A Complete Theoretical and Practical Piano School in Three Parts, from Elementary Education to the Highest Degree, Equipped with All the Necessary Examples Specially Created for this Purpose, Compiled by Carl Czerny" Оp. 500 (1839). As if confirming the title of this fundamental work corresponding to its content, N. Terentyeva testifies that "it has collected the most important rules on piano art, useful for every pianist and a wide range of pedagogical and aesthetic problems back in the day" (1978, p. 11).
The secret of the constant interdisciplinary interest in C. Czerny's etudes is seen in the following: their historical value, since together they give an idea of pianism development interacting with the half-century composition practice; in consistency inherent in the author's collections allowing to guide a teacher on the path of mastering the piano art playing step by step; in focusing on piano apparatus formation tasks and mastering all types of motility and texture formulas (unlike M. Clementi's "exercises" and I. Kramer's character etudes) in order to achieve technique freedom and perfection; many of them contain a complex of other musical and performing means along with motility skills, expanding the field of training tasks and linking them with purely technical ones into one subordination system preparing students for competent understanding of literary opuses. However, according to L. Bulatova, С. Czerny's etudes are "complete musical and artistic miniatures, an artistic detail containing the idea of improving a selected, single phenomenon" (Bulatova, 1991, p. 63). Obviously, the true combination of the instructive and artistic in C. Czerny's etudes prompts the researcher to characterize the famous Viennese teacher as a "classic" of this genre, the founder of the base "where all the romantic trend studies grew over time" (ibid).
In this regard, E. Semenova's statement seems to be appropriate: "<...> the "piano technique" concept expands its content, denoting not only various technical formulas virtuoso mastery, but first of all characterizing the level of possibilities of performance sound mastery, a pianist's articism needed for a vivid musical images disclosure" (Semenova, 2012, p. 128). It is also significant that, according to L. Bulatova, there is a reflection of piano texture forming process found in C. Czerny's etudes, "whose fantastic variety created by the author was determined by its remarkable ability to embody the artistic expressiveness connected with meaning change and style sound" (Bulatova 1991, p. 64). Thus, C. Czerny's etudes appear as musical works, whose genre semantics is determined by its functional orientation.
The brief review of the most historically significant etude collections from the late 18 th to the early 19 th century, being the basis of piano pedagogy, proves the inherent didactic potential steadiness and, therefore, reasonable including this genre samples into the academic student repertoire at all stages of their professional and performing development.

Conclusions
The auxiliary function of instructive etude does not in any way exclude its being a special kind of musical work. Its originality is focused on a stable performance base formation among young musicians and piano culture above all. The semantic genre "cutting" and its vertical projection are hierarchical which is impossible with skipping separate stages of learning. In addition to that, each stage requires a higher level of complexity from elementary playing skills building to achieving mastery in performance analysis methods. Instructive etudes complex contains a paradigm reminding a system of expanding circles, where new problems can be dealt only based on competently solved included previous tasks. Thus, the didactic potential of this genre turns out to be essentially inexhaustible, which makes it possible to successfully refer to its samples at all stages of a pianist's professional development.