The Clavichord.
"Bebung."
The instruments for which the first group of writers down to Haydn and Mozart wrote, were the immediate precursors of the pianoforte—the clavichord, spinet, or virginal, and harpsichord. The last was the concert instrument, and stood in the same relationship to the others that the grand pianoforte of to-day stands to the upright and square. The clavichord was generally the medium for the composer's private communings with his muse, because of its superiority over its fellows in expressive power; but it gave forth only a tiny tinkle and was incapable of stirring effects beyond those which sprang from pure emotionality. The tone was produced by a blow against the string, delivered by a bit of brass set in the farther end of the key. The action was that of a direct lever, and the bit of brass, which was called the tangent, also acted as a bridge and measured off the segment of string whose vibration produced the desired tone. It was therefore necessary to keep the key pressed down so long as it was desired that the tone should sound, a fact which must be kept in mind if one would understand the shortcomings as well as the advantages of the instrument compared with the spinet or harpsichord. It also furnishes one explanation of the greater lyricism of Bach's music compared with that of his contemporaries. By gently rocking the hand while the key was down, a tremulous motion could be communicated to the string, which not only prolonged the tone appreciably but gave it an expressive effect somewhat analogous to the vibrato of a violinist. The Germans called this effect Bebung, the French Balancement, and it was indicated by a row of dots under a short slur written over the note. It is to the special fondness which Bach felt for the clavichord that we owe, to a great extent, the cantabile style of his music, its many-voicedness and its high emotionality.
Quilled instruments.
Tone of the harpsichord and spinet.
Bach's "Music of the future."
The spinet, virginal, and harpsichord were quilled instruments, the tone of which was produced by snapping the strings by means of plectra made of quill, or some other flexible substance, set in the upper end of a bit of wood called the jack, which rested on the farther end of the key and moved through a slot in the sounding-board. When the key was pressed down, the jack moved upward past the string which was caught and twanged by the plectrum. The blow of the clavichord tangent could be graduated like that of the pianoforte hammer, but the quills of the other instruments always plucked the strings with the same force, so that mechanical devices, such as a swell-box, similar in principle to that of the organ, coupling in octaves, doubling the strings, etc., had to be resorted to for variety of dynamic effects. The character of tone thus produced determined the character of the music composed for these instruments to a great extent. The brevity of the sound made sustained melodies ineffective, and encouraged the use of a great variety of embellishments and the spreading out of harmonies in the form of arpeggios. It is obvious enough that Bach, being one of those monumental geniuses that cast their prescient vision far into the future, refused to be bound by such mechanical limitations. Though he wrote Clavier, he thought organ, which was his true interpretative medium, and so it happens that the greatest sonority and the broadest style that have been developed in the pianoforte do not exhaust the contents of such a composition as the "Chromatic Fantasia and Fugue."
Scarlatti's sonatas.
The earliest music written for these instruments—music which does not enter into this study—was but one remove from vocal music. It came through compositions written for the organ. Of Scarlatti's music the pieces most familiar are a Capriccio and Pastorale which Tausig rewrote for the pianoforte. They were called sonatas by their composer, but are not sonatas in the modern sense. Sonata means "sound-piece," and when the term came into music it signified only that the composition to which it was applied was written for instruments instead of voices. Scarlatti did a great deal to develop the technique of the harpsichord and the style of composing for it. His sonatas consist each of a single movement only, but in their structure they foreshadow the modern sonata form in having two contrasted themes, which are presented in a fixed key-relationship. They are frequently full of grace and animation, but are as purely objective, formal, and soulless in their content as the other instrumental compositions of the epoch to which they belong.
The suite.