Among Bach’s numerous pupils the most noted, besides his own sons, were Krebs, Altnickol, Agricola, Vogler, and the theorists, Marpurg and Kirnberger. His most distinguished sons were, Wilhelm Friedemann, Carl Philipp Emanuel, Johann Christoph Friedrich, known as the Bückeburg Bach, and Johann Christian, called the Milanese Bach. Wilhelm Friedemann Bach (1710–84) was the eldest son of Sebastian Bach. He was a genius, and his father bestowed great care on his musical training, and had great hopes of his future. He studied at the St. Thomas School and university of Leipsic, where he distinguished himself in mathematics. For a number of years he held a position as organist at Dresden. In 1747 he became director and organist at Halle. In later years he led a wild and wandering life, and finally died in utter want and misery in Berlin. He was perhaps the greatest organist of his time, and was famous for his wonderful improvisations. He wrote a large number of compositions, many of which are preserved in the Berlin Royal Library, but few of which are published.

Carl Philipp Emanuel Bach was born at Weimar in 1714. In his youth he studied law thoroughly, and busied himself with music rather as an amateur than as one who intended to make it a profession. His attention was devoted chiefly to piano playing and the art of improvisation, which, thanks to his father’s rare teaching, he carried to the highest degree of perfection. He was destined, after all, to make music his life-work. He had hardly completed his university studies when he received an invitation from the crown prince of Prussia, afterward Frederick the Great, to accept a musical position at court. He accepted, and remained in his service for a number of years. In 1767 he became successor of Telemann as conductor of the opera at Hamburg, where he remained until his death. By his daily practice in improvisation, Emanuel Bach acquired a freedom and elegance of style equalled by no other German master except his father. His position and intercourse with the best society were not without good influence on his music. He possessed hardly a tithe of his father’s genius; but, as he lived more in the world, he became a man of fashion and popularity. In his day his name was far better known than that of his father, and musicians looked upon Emanuel Bach as the great authority. Even Mozart said of him: “He is the father; we are mere children. Those of us who can do anything right in music have learned it of him. Although we could not be satisfied nowadays to do what he did, nevertheless, no one was able to equal him in what he did.” He was an inferior vocal composer. It was chiefly as a clavichord player and composer that he took first rank. His refined style and uncommon finish of execution excited universal wonder. Emanuel Bach’s vocal works embrace two oratorios; twenty-two passions; sacred cantatas; Singspiele; sanctus for two choirs; sacred and secular songs, etc. His works for clavier are very numerous, consisting of sonatas, concertos and solos. Eighteen of his orchestral compositions are published by Breitkopf and Härtel.

Emanuel Bach’s talent as a teacher was evinced in his celebrated treatise, “On the True Art of Playing the Clavichord,” which contains the principles of all good piano playing. But his greatest services to modern music were rendered in his sonatas and symphonies, in which he not only enlarged the form, but also increased the means of expression and of instrumental effects. Emanuel Bach exercised a great influence on the clavier sonata, and first brought it into prominence. The so-called sonatas of Domenico Scarlatti were single, brilliant movements which resembled the prelude. Sebastian Bach’s sonatas for the organ, clavier and violin, etc., in three or four movements, were more or less fugal and strict. Emanuel Bach combined the solidity of the style of his father with the brilliancy and lightness of Scarlatti. Although it remained for Haydn to develop fully the principle of free thematic music, the germ of the modern style existed in the sonatas of Emanuel Bach. The habit of improvisation gave full scope to the play of his imagination, and consequently his works are characterized by a certain ease and brilliancy which distinguish him from his predecessors. He made more use than formerly of contrasted themes in the several movements of the sonata, and they were brought into relation to each other by means of free passages. His “Salon” style is distinguished for its elegance and grace, ornateness and playfulness, and well represents the polite world in which he lived.

Having traced the early development of organ and clavier music, we will turn our attention, for a moment, to the growth of orchestral music to the advent of Haydn, and the so-called classical period of modern instrumental music. During the first half of the seventeenth century the instruments used in connection with the opera served a subordinate position. The accompaniments of the recitatives and arias consisted of a ground bass (basso continuo) for chittarone, organ, clavier, etc., which supplied the chords indicated by figures. In the opera-madrigals the orchestral accompaniment was simply a reproduction of the vocal parts, on wind and stringed instruments. In the course of time instrumental ritornelli were introduced to relieve the solo voices, and melodic phrases were given to the instruments. The first operas generally opened with a flourish of trumpets or with a madrigal played by the instruments alone; sometimes dances played by the instruments were introduced in course of the opera.

The opera overture was invented subsequently, probably by Lully. It consisted, at first, of three short movements, slow, quick, slow. Scarlatti and his contemporaries adopted the overture, and changed the order of the movements to allegro, adagio, allegro.

With the perfection of the violin and the other stringed instruments, about the beginning of the eighteenth century, solo playing became more and more artistic. With Corelli, sonatas and suites for one or more violins and clavier became the fashion. At this time the orchestra was well organized, so far as the true relation of the string band to the wind instruments is concerned.

The cultivation of chamber music was encouraged by titled and fashionable people, and virtuosos on various orchestral instruments appeared. Thus instrumental music began to be cultivated independent of the opera and church music.

The three-movement form suggested by the overture was the type of this independent orchestral music, under the names of symphony, concerto, or suite. Such were the orchestral symphonies of Sammartini, the famous Milanese conductor of the first half of the eighteenth century. His is the first prominent name in this field. He was soon followed by German composers, among whom were Stamitz, J. C. Bach, Abel, Wagenseil, Cannabich and Emanuel Bach.

Among noted German instrumental soloists of this period were Johann Georg Pisendel (1687–1755), who was celebrated as a violinist, and composed concertos for solo violin and string quartet, which were considered as among the best of that time.