The Acoustics of the Harpsichord: Response Curves and Modes of Vibration

Air and structural modes of a harpsichord

“…Previous studies on the acoustics of harpsichords can be found in papers by Kellner (1976), Fletcher (1977), Spencer ( 1981 ), and Kottick ( 1985); and of its relative, the clavichord, by Thwaites ( 1981 ) and Thwaites and Fletcher ( 1981 ). These are valuable articles, but they are limited either to a few aspects of the acoustical behavior of harpsichords, or to purely theoretical considerations without experimental verification.…”

“…But since every soundboard is different, harpsichords vary in their output response. The variety in the peaks in response curves (see Kottick, 1985), undoubtedly indicates individual qualities.…”

“…Therefore, since 1976, the first two authors of this paper, with considerable assistance from the second two, have attempted to better understand the mysteries of this instrument. We have gathered experimental data on soundboard and air resonances and their interaction by Our understanding of the harpsichord's behavior was enhanced by field work performed in 1980, when response curves and Chladni patterns were obtained for 39 harpsichords, both new and antique (Kottick, 1985). Until 1986, the information we gathered on the vibrational behavior of the instrument was limited to the study of the force and motion at one location at a time.…”

“…To facilitate the experimental measurements, the lid, which normally reflects a great deal of sound out toward the listener, was set at 90 deg to the instrument, rather than at the more usual 45 deg. The French harpsichord mentioned is identified as Hyman K10 in Kottick (1985).…”

“…Placed on the bridge pin for each string in turn, it applied a sinusoidal excitation with a frequency equal to the fundamental of the string. A microphone was placed 3 m above the soundboard to record the acoustics harpsichord's output response (see Kottick, 1985).…”