La costruzione di un Clavecin Roïal
A Clavecin Roïal is a large German square piano with five octaves (FF-g3). The instrument has a hammer action of the Stoßmechanik type, but it works differently from the better known Englisch hammer action.
The sound is generated by bare wooden hammer heads, triangular in cross-section. The strings are only damped when using a knee lever to engage the dampers. With a second knee lever one can engage a so called harp register (a frame with cloth fringes on its front site which can be lowered to the strings until the fringes touch them). With a third knee lever one can move small pieces of leather between the strings and the hammer, this register is called the moderator. There is also a swell, an internal cover made of cardboard and silk which sits above the soundboard and opens to give a crescendo effect or sudden fortissimo.
The surviving examples are all of extremely good workmanship. Most of them have unusual veneers with beautiful inlay work, the surfice polished and decorated with smart brass hinges. In the Bachhaus in Eisenach a Clavecin Roïal from 1788 has survived. It is built in the more traditional clavichord style with an oak case and visible dovetail joints, the style chosen for this copy.
The instrument was given the name Clavecin Roïal by its maker, the Dresden builder Johann Gottlob Wagner (1741–1789). He worked together with his younger brother Christian Salomon (1754–c.1800), who continued the business after Johann Gottlob's death. Around 10 instruments of the brothers Wagner have survived.
Wagner published for the first time in 1775 a description of this instrument which four years later, in 1779, was printed in Johann Nicolaus Forkel's Musikalisch-kritischer Bibliothek.
„Already in the year 1775 an organ and instrument maker from Dresden, Mr. Wagner, has through an announcement described a new kind of Clavecin (harpsichord) which he invented and which he named on advice of a great composer and musician Clavecin roïal. The whole construction will be understood best with his own description; we reproduce it here literally.”
“Already last year a newly invented musical instrument, which one of the greatest living musicians [C. P. E. Bach?] gave the name Clavecin Roïal, was announced by the person mentioned before[…]. Instead of the plectra's or the brass tangents in this new instrument the notes sound in the various registers thanks to wooden hammers […]. If he [musician] is good in improvisation, rich in imagination and knows how to use the the long sound of the bass artfully, will be able to play the most pleasant harmonies there are to be heard.”
Carl Philipp Emanuel Bach refers to the instrument in the second part of his book Die wahre Art das Clavier zu spielen published in 1762.
“The undamped stop of the Fortepiano is the most agreeable and, if one knows how to use the necessary caution because of the reverberation, it is the most beautiful for improvising.”
From CPE Bach's inventory we know that he owned a Clavecin Roïal from the then famous instrument maker Friederici from Gera, of whom unfortunately no Clavecin Roïal has survived.
„A Fortepiano or Clavecin Roial from the old Friederici, made of oak with a beautiful sound.”
The Clavecin Royal was built in big numbers until around 1796. It is very important for the historical performance practice of the late 18th century but it also plays, together with Johannes Zumpe's English square, a major role in the history of the piano.
Recent research on the subject has been undertaken by Michael Latcham, Michael Cole, Sabine Klaus and Pablo Gómez Ábalos. The latter is the initiator of the project which won the 2017 Leonardo Grant for Researchers and Cultural Creators of the BBVA Foundation (Spain).