Bach preferred the Clavichord to the Harpsichord, which, though susceptible of great variety of tone, seemed to him lacking in soul. The Pianoforte was still in its infancy and too coarse.(128) Both for practice and intimate use he regarded the Clavichord as the best instrument and preferred to express on it his finest thoughts. He held the Harpsichord, or Clavicembalo, incapable of the gradations of tone obtainable on the Clavichord, an instrument which, though feeble in quality, is extremely flexible.
No one could adjust the quill plectrums of his Harpsichord to Bach’s satisfaction; he always did it himself. He tuned his Harpsichord and Clavichord, and was so skilful in the operation that it never took him more than a quarter of an hour. It enabled him to play in any key he preferred, and placed the whole twenty-four of them at his disposal, so that he could modulate into the remoter as easily and naturally as into the more nearly related keys. Those who heard him frequently could hardly detect the fact that he had modulated into a distant key, so smooth were his transitions. In chromatic movements his modulation was as easy and sequent as in diatonic. His _Chromatic Fantasia,_ which is now published,(129) bears out my statement. In his extemporisation he was even freer, more brilliant and expressive.
When he played his own music Bach usually adopted a brisk pace. He contrived to introduce so much variety that every piece became a sort of conversation between its parts. If he wished to express deep emotion he did not strike the notes with great force, as many do, but expressed his feeling in simple melodic and harmonic figures,(130) relying rather on the internal resources of his art than external dynamics. Therein he was right. True emotion is not suggested by hammering the Clavier. All that results is that the notes cannot be heard distinctly, much less be connected coherently.
What has been said regarding Bach’s admirable Clavier playing applies generally to his skill as an organist. The Clavier and Organ have points in common, but in style and touch are as different as their respective uses. What sounds well on the Clavier is ineffective on the Organ, and vice versa. The most accomplished Clavier player may be, and usually is, a bad organist unless he realises the differing natures of the two instruments and the uses they serve. I have come across only two men who can be regarded as exceptions to this general rule—Bach and his eldest son, Wilhelm Friedemann. Both were finished Clavier performers, but no trace of the Clavier style was apparent when they played the Organ. Melody, harmony, and pace were carefully selected with due regard to the nature and distinctive use of each instrument. When Wilhelm Friedemann played the Clavier his touch was elegant, delicate, agreeable. When he played the Organ he inspired a feeling of reverent awe. On the one he was charming. On the other he was solemn, impressive. So also was his father, and to an even greater degree. Wilhelm Friedemann was a mere child to him as an organist, and frankly admitted the fact.(131) The music that extraordinary man wrote for the Organ is full of dignity, awe-inspiring, saturated with the atmosphere of devotion. His improvisation was even more inspired, dignified, and impressive: for then his imagination was untrammelled by the irksomeness of expressing himself on paper. What is the essence of this art? Let me, though imperfectly, attempt an answer.