Good Sound

What constitutes good sound at the clavichord? Framed in terms of the mechanics of the instrument, the answer does not have to be subjective. Contact between the tangent and the strings that is firm and sustained enough to set the strings vibrating—for the full length of the note—creates good sound. In order to maintain this contact, the player actually has to raise the strings a little bit with the tangent. Keeping steady pressure on the strings results in a note with a steady pitch, while raising and lowering the strings changes the sounding pitch and creates the Bebung or vibrato effect for which the clavichord is famous. In either case, sound is sustained throughout the length of the note by the tangent’s firm contact with the strings. If sustained sound is good, its opposite, blocked sound, is bad. Blocking occurs when the tangent does not introduce enough kinetic energy into the strings to set them vibrating, or when the contact between the tangent and the strings is broken too soon. The resulting note sounds like a dull thump, or stops sounding altogether. Furthermore, if the tangent is raised only to the level of the strings, and not pushed a little above that level, the contact between tangent and string can be intermittently broken, and an unpleasant buzzing sound results as the strings vibrate against the tangent. Figure 5.1 illustrates the mechanics of good and blocked sound.

Sound Production, String Tension, and Touch

It is difficult to define completely the original touch characteristics of an historical clavichord. Many parameters that affect touch are ephemeral: we can no longer know with certainty what kind of listing cloth was used between the strings, the pattern in which it was woven, the pitch to which the instrument was tuned, or the thickness of the cloth under the backs of the keys that sets the final distance between the tops of the tangents and the strings. All of these factors affect how it feels to play the instrument.