The lids of pianos and harpsichords as acoustic transformers
Edith L. R. Corliss, Charles H. Corliss · The Journal of the Acoustical Society of America · 1983
The lid of a grand piano may be closed altogether on the case, removed, or raised to a fixed position by a stick. Many larger instruments are equipped with a short stick as an alternative to the long stick. Raising the lid to these alternative positions changes the tone color to an extent perceptible to the player and the audience. This effect is measured more readily with a harpsichord because the plucking action is essentially independent of the player's touch. Using a harpsichord built by C. Randall Taylor in 1966, the authors have investigated the effect of adjusting the lid to a number of positions. The change produces measurable alterations in the output. The effect is similar to horn loading on a loudspeaker, and will be discussed from this standpoint.