In designing his oval spinet, Bartolomeo Cristofori (1655–1731) sought to produce a relatively small instrument with long bass strings, two 8′ registers with a difference in timbre equal to that obtainable with a harpsichord, a symmetrical distribution of the tensions on the soundboard, and an aesthetically appealing and elegant appearance.
The longest string is placed in the center of the soundboard, while the strings move towards the acute in symmetrical alteration to the left and to the right; they therefore require a complicated action system for the movement of the key levers to be transmitted to the appropriate jacks.
All of the first register’s strings are arranged in order towards the back side, while the second register’s strings progress from the center towards the front side—it is the two registers, and not the sequence of notes, that are symmetrical with respect to the center. The selection of the registers is accomplished by sliding the keyboard, which activates a counter-lever system.
This according to “Bartolomeo Cristofori: La spinette ovali del 1690 / Bartolomeo Cristofori’s 1690 oval spinet” by Gabriele Rossi-Rognoni, an essay included in Bartolomeo Cristofori: La spinetta ovale del 1690—Studi e ricerche / The 1690 oval spinet—Study and research (Firenze: Ministero per i Beni e le Attività Culturali, 2002).
Above, a replica built by Tony Chinnery and Kerstin Schwarz. Below, a brief documentary on Cristofori and his instruments.
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