The clavichord worked on the same principle. At the back end of each key lever was an upright tangent, at first of wood, later of metal, which, when the key was depressed, sprang up against the wire string stretched above it. The blow of this tangent caused the wire to vibrate and produce sound; and at the same time the tangent determined the length of the string which was to vibrate, just as the finger determines the length of a violin string by stopping it at some point on the fingerboard. The strings of the clavichord were so stretched that of the two lengths into which the tangent might divide them, the longer lay to the left. It was this longer length which was allowed to vibrate, giving the desired pitch; the shorter length to the right being muffled or silenced by strips of felt laid or woven across the strings. Thus the little tangents at the back end of the keys performed the double function of sounding the string by hitting it and determining its pitch by stopping it. Thus, too, one string served several keys. By the middle of the sixteenth century the normal range was four full octaves, from C to c3. There were many more keys than strings, which was a serious restriction upon music for the instrument; for notes which lay as closely together as, let us say, C-sharp and E could not be sounded at once, since both must be played upon the same string. Not until practically the beginning of the eighteenth century were clavichords made with a string for each key. They were then called bundfrei, in distinction from the older clavichords, which had been called gebunden.
The clavichord always remained square or oblong in shape, and for many years had no legs of its own, but was set upon a table like a box—hence one of its old names, Schachbrett, chess-board. The case was often of beautiful wood, sometimes inlaid and adorned with scrolls, and the under side of the cover was often painted with allegorical pictures and pious or sententious mottoes. The keys were small, the touch extremely light. The tone, though faint, had a genuine sweetness and an unusual warmth; and, by a trembling up and down movement of the wrist while the finger still pressed the key, the skilled player could give to it a palpitating quality, allied to the vibrato of the human voice or the violin, which went by the name of Bebung. This lifelike pulsing of tone was its most precious peculiarity, one which unhappily is lacking to the pianoforte, in most ways immeasurably superior. Hardly less prized by players who esteemed fineness of expression above clearness and brilliance, was the responsiveness of its tone to delicate gradations of touch. This made possible fine shading and intimate nuances. On this account it was highly valued, especially in Germany, as a practice instrument, upon which the student could cultivate a discriminating sensitive touch, and by which his ear could be trained to refinement of perception.
The tone of the clavichord was extremely delicate. Its subtle carrying quality could not secure it a place in the rising orchestras, nor in the concert hall. It belonged in the study, or by the fireside, and in such intimate places was enshrined and beloved by those who had ears for the finer whisperings of music. But not at once was it so beloved in the course of the early development of our instrumental music. Frail and restricted, it was but a makeshift to bring within the circle of the family the growing music of its powerful overshadowing prototype—the organ.
The harpsichord was quite different and shared with its weaker sister only the keyboard and the wire strings. It was in essence a harp or a psalter played by means of a keyboard. The strings were tuned as in a harp and were plucked by means of quills attached to the key-levers. The tone was sharp and dry and could not be influenced by the player’s touch. Instruments of this nature seem first to have been made in England. At any rate it was in England that a considerable literature was first written for them. The English virginals are small harpsichords. The origin of the quaint name is no longer carried back to the love of the Virgin Queen Elizabeth for such music as the instrument could produce. Nor is it likely that it was so named on account of its size (it could be held on the lap), whereby it recommended itself to the convenience of young ladies with a musical turn. Most likely its name is due to its range, which was the high range of a young woman’s voice, an octave higher than the centre octave of the organ.
The harpsichord, or, more exactly, instruments which were plucked by quills attached to key-levers, went by many names besides virginals. In Italy it was called the clavicembalo, later the gravicembalo, or merely cembalo; in France the clavecin; in Germany the Kielflügel. The more or less general name of spinet seems to be derived from the name of a famous Italian maker working at the beginning of the sixteenth century, Giovanni Spineta, of Venice.
These instruments developed side by side with the clavichord but to much greater proportions. In the course of time several strings were strung for one note, one or all of which might be used, at the discretion of the player, by means of stops similar in appearance and use to organ stops. Sometimes the extra strings of a note would be tuned at the octave or upper fifth, permitting the player to produce the mixture effects common to the organ. Many instruments were fitted with two and even three banks of keys, which operated upon distinct sets of strings, or might bring some special sort of quill into play; and these keyboards could be used independently for contrast, or coupled for volume, or the music might be divided upon them. There were also pedals for special effects.
There was great need of these numerous sets of strings, these various sorts of quills, these keyboards and devices for coupling them, because the mechanism of the harpsichord action was unsusceptible to the fine gradations of touch. It was essentially a mechanical instrument; its range of what we may call tone-shading was defined by the number of purely mechanical adjuncts with which it happened to be furnished. Variety depended upon the ingenuity of the player in bringing these means into play. This does not, of course, imply that there was no skill in ‘touching’ the harpsichord. The player had to practice hours then as now, to make his touch light and, above all, regular and even. The slightest clumsiness was perhaps even more evident to the ear of the listener in the frosty tones of the harpsichord than it would be today in the warmer and less distinct tone of the pianoforte. But once this evenness and lightness attained, the science of ‘touch’ was mastered and the player proceeded to search out musical effects in other directions.
In the course of these years from 1500 to 1750 it was made more and more to impress the ear by means of added strings and stops and sets of quills, till it became the musical keystone of chamber music, of growing orchestra and flowering opera. At the same time it was made ever more beautiful to the eye. It grew fine in line and graceful in shape; its wood was exquisitely finished and varnished; it was inlaid with mother-of-pearl, and was beautifully decorated and enscrolled. The keys were small and usually of box-wood, the diatonic keys often black, the chromatic keys white with mother-of-pearl or ivory. Artisan and artist lavished their skill upon it. What a centre it became! How did it sound under the fingers of Count Corsi, behind the scenes of his private theatre in the Palazzo Corsi at Florence, while noble men and gentle ladies sang out the story of Orpheus and Eurydice to a great king of France and Maria de Medici his bride, when the first Italian opera was sung in public?
The great Monteverdi’s antique orchestra clustered about two harpsichords, only a few years later in Mantua, when ‘Ariadne’ brought tears to the eyes of princes. How was it in Venice when Cavalli was of all musicians the most famous, in the public theatre of San Cassiano? It supported the oratorios of Carissimi in Rome, and his cantatas as well. And in 1679 the great Bernardo Pasquini, organist of the people and the senate of Rome, presided at the harpsichord when the new theatre of Capranica was opened, and the amiable Corelli led the violins. And so they all presided at the harpsichord, these brilliant writers of operas now of all music the most discarded, down to the days of the great Scarlatti in Naples, of Handel in London, of Keiser and Graun in Hamburg, and Hasse, the beloved Saxon, in Dresden. Lully the iron-willed, he who watched alertly the eyebrow of great King Louis XIV of France, sat at his harpsichord in his lair and spilled snuff on the keys while he wrought his operas out of them. Then there was Mattheson, who would sing Antony, and die in the part, yet would come back and play the harpsichord in the Hamburg opera house orchestra after all the house had seen him die. He was determined to sit at the harpsichord, in the centre of the orchestra, and accompany his Egyptian queen to death, when all knew he should rightfully be waiting for her in Heaven with a lyre!
The harpsichord was indeed the centre of public music of orchestra and opera. Even after a race of virtuosi had pulled it to the fore as a brilliant solo instrument it still held its serviceable place in the orchestra. When in the course of time overtures became symphonies, it was still from the harpsichord that the conductor, usually the composer, led the performance of them. Gluck wished to banish it from the orchestra of the opera house; but, when Haydn came to London in 1790 and again in 1794 to lead a performance of his specially composed symphonies, he sat at the instrument which, more than any other, had assisted at the growth of independent instrumental music—at the harpsichord, now slowly but surely withdrawing into the background before the victorious pianoforte.