Harpsichord | multiple 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. This provides two advantages: the ability to vary volume and ability to vary tonal quality. Volume is increased when the mechanism of the instrument is set up by the player (see below) 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
A particularly vivid effect is obtained when the strings plucked simultaneously are an
When describing a harpsichord it is customary to specify its choirs of strings, often called its
Harpsichords with more than one keyboard (this usually means two keyboards, stacked one on top of the other in a step-wise fashion, as with pipe organs) provide flexibility in selecting which strings play, since each manual can be set to control the plucking of a different set of strings. In addition, such harpsichords often have a mechanism (the "coupler") 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 (also used in Baroque Flanders) 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" (not shown in the Figure). A lute stop is used to imitate the gentle sound of a plucked
The use of multiple manuals in a harpsichord was not originally provided for the flexibility in choosing which strings would sound, but rather for