Harpsichord


A harpsichord is a keyboard instrument that makes its sound by plucking a set of strings. In a harpsichord, depressing a key raises its back end within the instrument, which in turn lifts one or more jacks, each a thin strip of wood holding a small plectrum made from quill or plastic; each plectrum plucks a single string. The strings are under tension on a soundboard, which is mounted in a wooden case; the soundboard amplifies the vibrations from the strings so that the listeners can hear them. Harpsichord often include more than one choir of strings. Various devices are used to select which choir will sound when playing; these can include simple levers, or in more elaborate instruments the deployment of more than one keyboard.
The term denotes the whole family of similar plucked-keyboard instruments, including the smaller virginals, muselar, and spinet. The harpsichord was widely used in Renaissance and Baroque music, both for purposes of accompaniment and as a solo instrument. During the Baroque era, the harpsichord was a standard part of the continuo group. During the late 18th century, with the spread of the piano, the harpsichord gradually disappeared from the musical scene. In the 20th century, it made a resurgence, being used in historically informed performance of older music, in new compositions, and in certain styles of popular music.

History

The harpsichord was most likely invented in the late 14th century. The earliest instruments were quite small and sounded at relatively high pitch. By the 16th century, harpsichord makers in Italy had evolved a design that survived well into later centuries: lightweight instruments with thin case walls and low tension brass strings arranged in two choirs with a single manual. A different approach was taken in the Southern Netherlands starting in the late 16th century, notably by the Ruckers family. Their harpsichords used a heavier construction and produced a more powerful and distinctive tone with higher tension steel treble stringing. These included the first harpsichords with two keyboards, used for transposition.
The Flemish instruments served as the model for 18th-century harpsichord construction in other nations. In France, the double keyboards were adapted to control different choirs of strings, making a more musically flexible instrument. Instruments from the peak of the French tradition, by makers such as the Blanchet family and Pascal Taskin, are among the most widely admired of all harpsichords, and are frequently used as models for the construction of modern instruments. In England, the Kirkman and Shudi firms produced sophisticated harpsichords of great power and sonority. German builders such as Hieronymus Albrecht Hass extended the sound repertoire of the instrument by adding sixteen-foot and two-foot choirs; instruments by the German builder Michael Mietke have recently served as models for modern builders.
Around the year 1700 the first piano was built by Bartolomeo Cristofori. In the piano, the strings are not plucked but rather are struck with hammers, which makes it possible for the player to control the volume of each note. With time and changes in compositional style, the expressive nuances made possible by the piano came to be increasingly valued, and by the late 18th century the piano had largely supplanted the harpsichord. The harpsichord, now considered obsolete, almost disappeared from view for most of the 19th century. An exception was its continued use in opera for accompanying recitative, but the piano sometimes displaced it even there.
Twentieth-century efforts to revive the harpsichord began with instruments that used piano technology, with heavy strings and metal frames. Starting in the middle of the 20th century, ideas about harpsichord making underwent a major change, when builders such as Frank Hubbard, William Dowd, and Martin Skowroneck sought to re-establish the building traditions of the Baroque period. Harpsichords of this type of historically informed building practice dominate the current scene.

Mechanism

Harpsichords vary in size and shape, but all have the same basic mechanism. The player depresses a key that rocks over a pivot in the middle of its length. The other end of the key lifts a jack that holds a small plectrum, which plucks the string. When the player releases the key, the far end returns to its rest position, and the jack falls back; the plectrum, mounted on a tongue mechanism that can swivel backwards away from the string, passes the string without plucking it again. As the key reaches its rest position, a felt damper atop the jack stops the string's vibrations. These basic principles are explained in detail below.
  • The keylever is a simple pivot, which rocks on a balance pin that passes through a hole drilled through the keylever.
  • The jack is a thin, rectangular piece of wood that sits upright on the end of the keylever. The jacks are held in place by the registers. These are two long strips of wood, which run in the gap between pinblock and bellyrail. The registers have rectangular mortises through which the jacks pass as they can move up and down. The registers hold the jacks in the precise location needed to pluck the string.

  • In the jack, a plectrum juts out almost horizontally and passes just under the string. Historically, plectra were made of bird quill or leather; many modern harpsichords have plastic plectra.
  • When the front of the key is pressed, the back of the key rises, the jack is lifted, and the plectrum plucks the string.
  • The vertical motion of the jack is then stopped by the jackrail, which is covered with soft felt to muffle the impact.

  • When the key is released, the jack falls back down under its own weight, and the plectrum passes back under the string. This is made possible by having the plectrum held in a tongue attached with a pivot and a spring to the body of the jack. The bottom surface of the plectrum is cut at a slant; thus when the descending plectrum touches the string from above, the angled lower surface provides enough force to push the tongue backward.
  • When the jack arrives in fully lowered position, the felt damper touches the string, causing the note to cease.

    Strings, tuning, and soundboard

Each string is wound around a tuning pin at the end nearest the player. When rotated with a wrench or tuning hammer, the tuning pin adjusts the tension so that the string sounds the correct pitch. Tuning pins are held tightly in holes drilled in the pinblock or wrestplank, an oblong hardwood plank. Proceeding from the tuning pin, a string next passes over the nut, a sharp edge that is made of hardwood and is normally attached to the wrestplank. The section of the string beyond the nut forms its vibrating length, which is plucked and creates sound.
At the other end of its vibrating length, the string passes over the bridge, another sharp edge made of hardwood. As with the nut, the horizontal position of the string along the bridge is determined by a vertical metal pin inserted into the bridge, against which the string rests. The bridge itself rests on a soundboard, a thin panel of wood usually made of spruce, fir or—in some Italian harpsichords—cypress. The soundboard efficiently transmits the vibrations of the strings into vibrations in the air; without a soundboard, the strings would produce only a very feeble sound. A string is attached at its far end by a loop to a hitchpin that secures it to the case.

Multiple manuals and choirs of strings

While many harpsichords have one string per note, more elaborate harpsichords can have two or more strings for each note. When there are multiple strings for each note, these additional strings are called "choirs" of strings. Having multiple choirs provides two advantages: the ability to vary volume and the ability to vary tonal quality. Volume is increased when the mechanism of the instrument is set up by the player so that the press of a single key plucks more than one string. Tonal quality can be varied in two ways. First, different choirs of strings can be designed to have distinct tonal qualities, usually by having one set of strings plucked closer to the nut, which emphasizes the higher harmonics, and produces a "nasal" sound quality. The mechanism of the instrument, called "stops", permits the player to select one choir or the other. Second, having one key pluck two strings at once changes not just volume but also tonal quality; for instance, when two strings tuned to the same pitch are plucked simultaneously, the note is not just louder but also richer and more complex.
A particularly vivid effect is obtained when the strings plucked simultaneously are an octave apart. This is normally heard by the ear not as two pitches but as one: the sound of the higher string is blended with that of the lower one, and the ear hears the lower pitch, enriched in tonal quality by the additional strength in the upper harmonics of the note sounded by the higher string.
When describing a harpsichord, it is customary to specify its choirs of strings, often called its disposition. To describe the pitch of the choirs of strings, pipe organ terminology is used. Strings at eight-foot pitch sound at the normal expected pitch; strings at four-foot pitch sound an octave higher. Harpsichords occasionally include a sixteen-foot choir or a two-foot choir. When there are multiple choirs of strings, the player is often able to control which choirs sound. This is usually done by having a set of jacks for each choir, and a mechanism for "turning off" each set, often by moving the upper register sideways a short distance, so that their plectra miss the strings. In simpler instruments, this is done by manually moving the registers, but as the harpsichord evolved, builders invented levers, knee levers and pedal mechanisms to make it easier to change registration.
Harpsichords with more than one keyboard provide flexibility in selecting which strings play, since each manual can be set to control the plucking of a different set of strings. This means that a player can have, for instance, an 8' manual and a 4' manual ready for use, making it possible to switch between them to obtain higher pitches or different tone. In addition, such harpsichords often have a mechanism that couples manuals together, so that a single manual plays both sets of strings.
The most flexible system is the French "shove coupler", in which the lower manual slides forward and backward. In the backward position, "dogs" attached to the upper surface of the lower manual engage the lower surface of the upper manual's keys. Depending on choice of keyboard and coupler position, the player can select any of the sets of jacks labeled in "figure 4" as A, or B and C, or all three.
The English "dogleg" jack system does not require a coupler. The jacks labeled A in Figure 5 have a "dogleg" shape that permits either keyboard to play A. If the player wishes to play the upper 8' from the upper manual only and not from the lower manual, a stop handle disengages the jacks labeled A and engages instead an alternative row of jacks called "lute stop". A lute stop is used to imitate the gentle sound of a plucked lute.
The use of multiple manuals in a harpsichord was not originally provided for the flexibility in choosing which strings would sound, but rather for transposition of the instrument to play in different keys.
The choice of the strings to be plucked is not the only way that sound quality can be modified. Some harpsichords may have a buff stop, which brings a strip of buff leather or other material in contact with the strings, muting their sound to simulate the sound of a plucked lute. This stop is typically controlled by an independent lever.
Some early harpsichords used a short octave for the lowest register. The rationale behind this system was that the low notes F and G are seldom needed in early music. Deep bass notes typically form the root of the chord, and F and G chords were seldom used at this time. In contrast, low C and D, both roots of very common chords, are sorely missed if a harpsichord with lowest key E is tuned to match the keyboard layout. When scholars specify the pitch range of instruments with this kind of short octave, they write "C/E", meaning that the lowest note is a C, played on a key that normally would sound E. In another arrangement, known as "G/B', the apparent lowest key B is tuned to G, and apparent C-sharp and D-sharp are tuned to A and B respectively.