[Chapter X]
Monophonic Style and the Sonata
Corelli and his violin style—C. P. E. Bach and his departures from polyphony—General plan and purpose of the early sonata—Haydn and his two principal themes—Mozart and song-melody—Clementi and the influence of his style—Beethoven's improvements in sonata form—His employment of instrumental music for emotional expression.
THE fundamental difference between the sonata and the polyphonic forms is that the sonata is written in the monophonic style. Polyphony is, indeed, occasionally employed, but the reigning style is that in which a melody, song-like in character and sung by a single part, is accompanied by other parts written in chord harmonies. The necessary repetition of the melodic ideas is made, not by the process of imitation, as in the fugue, but by what is called the cyclical method. In this a tune or a composition always returns to a restatement of the original theme from which it started. We have seen how this melodic style entered instrumental music in the days of Giovanni Gabrieli, and how Domenico Scarlatti transferred to the harpsichord the aria of the opera. From this time forward the monophonic style developed gradually from the initial impulse of the vocal solo. Composers who had not Bach's peculiar insight into polyphonic writing and profound genius for it naturally sought a form which would give their melodies coherence and intelligibility. The rapid development of the violin as a solo instrument was one of the influences in directing them along certain lines of construction. The violin naturally lent itself to a flowing, song-like style, yet it is easy to see how easily such a style would fall into monotony. The early violin composers, in their search after a form which would embrace coherency, variety, and contrast, did much toward assisting piano writers to reach the true method of composing.
Arcangelo Corelli (1653-1713) was the most influential of these early violin composers. He endeavored to unite in his works the attractive and popular features of church music, song, and the dances of his time. The attractiveness of making compositions out of different kinds of dance movements in alternation had presented itself to composers at an early date. Morley, in his "Plain and Easy Introduction to Practical Music" (1597), says: "It is effective to alternate pavanes with galliards, because the former are a kind of staid music ordained for grave dancing, and the latter for a lighter and more stirring kind of dancing." This alternation of dances is what first suggested to composers the plan of following a slow movement with a lively one, or vice versa. As these different kinds of dances differed in rhythm,—the pavanes, for instance, being in common and the galliard in triple measure,—composers grasped the idea that changes in rhythm would heighten the contrast between movements. The one thing that did not seem to be settled at the outset—and that was due to the newness of harmonic as opposed to polyphonic style—was the matter of key contrasts. Sometimes these early writers put all their dance movements in one key, making what we now call a "suite," and sometimes they did not.
Corelli wrote his sonatas most frequently in four movements. The composers who immediately succeeded him wrote more often in three movements, but preserved the alternation of rhythm and tempo. Corelli used only one subject in each movement, and the development of it was of a simple nature compared to the developments found in subsequent works. Later composers found that in order to secure the necessary amount of contrast and variety, together with those points of repose which are essential to artistic form in music, it was necessary to have two principal themes of contrasting nature. The development of these themes was confined to the first movement, while the other movements were less complex in design. The Germans were not wholly idle in advancing the sonata, but it is extremely difficult to ascertain how their work and that of the Italians affected one another. We know that a violin sonata by H. J. F. Biber, published in 1681, shows a well ordered sequence of contrasting movements. The first was a very slow one (largo), in contrapuntal style; the second, a passacaglia (theme and variations); the third, rhapsodical and declamatory; and the fourth, a gavotte. Dr. Parry has pointed out that Biber received his suggestions for the first movement from church polyphony, for the second and fourth from dances, and for the third from operatic declamation. This sonata, however, shows nothing of that methodic repetition of subjects and definite distribution of keys now regarded as indispensable; and in some respects Corelli's sonatas were of a distinctly higher type. Following the admirable analysis of Dr. Parry, I may state here that as early composers gradually perceived the possibilities of the sonata form, they evolved this scheme for their alternation of movement:—
1. Summons to attention, followed by appeal to intelligence through display of design.
2. Slow movement—appeal to the emotions.
3. Finale—lively reaction after emotion.
This treatment of the character of the movements grew out of the crude attempts of the earliest writers and was formulated in the concertos of Sebastian Bach, but more clearly in the piano sonatas of his son Carl Philip Emmanuel Bach. Previous to that, however, something had been done toward a definite arrangement of the distribution of keys. To this Domenico Scarlatti, who has already been mentioned, made some important contributions. His compositions called sonatas have a distinct melodic subject, and this is preserved throughout. His first movements foreshadow the shape which the first movements of the classical sonatas subsequently assumed. These movements are divided plainly into two parts, and each part is repeated. Each of them opens with an announcement of the melodic subject in the tonic key of the sonata. After stating his subject Scarlatti passes into a key closely related to that of the sonata, and gives a bit of what is called "passage work;" that is, florid or ornamental piano writing without a complete tune. The second part embarks upon a brief musical development of the subject by means of simple musical changes in its original shape, then modulates back into the original key, restates the beginning of the movement and comes to an end. One of the peculiarities of his works is that sometimes in the musical development ("working out," as it is called) of his theme he introduces a new melody, different from the first. Later writers caught at this idea and raised this second melody to an importance equal to that of the first.
Scarlatti's great contemporary, Johann Sebastian Bach, did not stand in the direct line of development of the piano sonata. As I have tried to show in writing of clavichord works, his sympathies when composing for a keyboard instrument were governed largely by his immense genius for the organ and his profound insight into the nature and scope of polyphonic composition. Nevertheless, his violin sonatas, the result of a close and admiring study of those of Corelli and Vivaldi, show a leaning toward the modern form. He followed the lines laid down by Corelli. All but one of his violin sonatas are in four movements, the first and third slow, and the second and fourth lively. The slow movements, as one would naturally expect from Bach, are intense in their emotional eloquence. But Bach's manner of development was almost always polyphonic, and this was hostile to the sonata method, which was radically monophonic.