Himself an enthusiastic amateur musician, Gottfried Zimmerman frequently re-equipped his establishment with the latest musical instruments for use by the Collegium and other musical guests. One of his prize possessions in the late 1720s was "a clavcymbel of large size and range of expressivity" which was a Leipzig attraction in itself. It was replaced by an "even finer instrument" in 1733. The baroque German harpsichord was undoubtedly a substantial and splendid instrument; our illustration at right (by Bolcioni, 1627) shows a three-manual instrument.
Solid and Sonorous
Contemporary music critic and commentator Jakob Adlung wrote in 1738: "The most beautiful harpsichord which I saw was that which Herr Vogler, Burgomeister in Weimar, took me to see and hear, an instrument for which Herr Vogler had himself drawn up the specification. The harpsichord consisted of two choirs of 8' strings and one of 4', with a compass of six octaves. One of the 8' set was on the upper keyboard, and the others played from the lower keyboard. The sound board was so thick that it gave the impression of being unable to sound, and yet, I never heard an instrument which had a more beautiful sound than this one. The interior of the case was reinforced with many elements of iron, especially the side of the tail, where the tension of the strings is strongest." Burgomeister Vogler (1695?-1765) was a pupil and admirer of J.S.Bach. He was organist at the court of Weimar until appointed Burgomeister in 1735.
Bach was naturally familiar with the instruments of the major harpsichord builders of his time, including Hamburg builder Hieronymus Albrecht Hass, of the preeminent North German family of stringed keyboard instrument makers. The 1760 Hass instrument here illustrated belonging to the Yale Collection, has two manuals with an extensive disposition of five choirs of strings (1x16', 2x8', 1x4', 1x2') with a separate soundboard for the 16' choir of strings. Buff stop on lower 8' and 16'. This fine instrument well represents the culmination of the German school, together with a fairly standardized specification.
Recent research has established that for his weekly concerts at Zimmermann' s Coffee House Bach had a double manual harpsichord (16', 3x8', 4') mounted on a pedal harpsichord (2x16', 3x8') made by Zacharias Hildebrandt, who was both harpsichord builder, and organ builder under the direction of Bach's friend and colleague Gottfried Silbermann.
Unlike the Flemish and French harpsichords, the baroque German harpsichord was a heavier, more solidly-built instrument with deeper sonority. The organ chorale, and organ music generally, played an important part in German religious life, and in terms of sonority the baroque German harpsichord could almost be considered as a domestic organ. Indeed Gottfried Silbermann, famed Saxon organ-builder, friend and contemporary of Bach, also built harpsichords in his Freiberg workshops.
The 16-foot stop
Recent musicological research has shown that Bach explicitly required a harpsichord with 16'-register for solo as well as for chamber music; he considered it important that music should have "fundament" - a good bass foundation. Thus he would most certainly have used the 16' register for the bass line when playing continuo or a sonata for harpsichord and violin or flute.
The Pedal Harpsichord
A pedal-harpsichord, that is, a harpsichord with an organ-type pedal-board, would have been found in the home of most German organists during the baroque period. Organ practice in churches was difficult; some willing collaborator had to be found, and paid, to pump the organ, and the church could be very cold in winter. Additionally, several present-day organists have confirmed that practice on the pedal-harpsichord is infinitely more demanding in terms of accuracy and precision than on the organ. Bach wrote his Six Trio Sonatas to improve the pedal technique of his son Wilhelm Friedemann. The manuscript of Bach's Passacaglia and Fugue, which according to Albert Schweizer vanished in the mid-1800's, was apparently headed Cembalo e pedale, clearly indicating performance on the pedal-harpsichord. Jakob Adlung, in Musica Mechanica Organoedi (1768), describes clavichords and harpsichords with separate pedals like an organ pedal-board. Bach possessed three of these, and according to Forkel, Bach "liked to improvise on a two-manual clavier with pedal". Our illustration shows an instrument currently in production by the firm of J.C. Neupert.
