Fretted Clavichord   

Compass:　GG-d'''

Size:1268mmW x375mmD x 85mmH
Reference: Drawings by Ute Singer, 1976
Model:　Johann Jacob Donat, 1700

The original compass of C to c''' is extended to GG to d'''. GG is located next left to C and AA/HH are on the back of the split sharp keys of C#/Eb. The sound board bridge stretches very close to the spine and the sound board is sandwiched between the bridge and the liner. It seems to effectively contribute to nicely spread the high frequency sound energy to whole body of the instrument.

Compass: C - f'''

Size: 1295mmW x 365mmD x 116mmH
Reference: Drawings by Richard N. Loucks, 1981

Model: Christian Gottlob Hubert, 1784
Presently, four clavichords made by C. G. Hubert in 1784 are found (K. Vermaiji). The original instrument, on which this replica was made, is the one kept in Edinburgh.  Other three clavichords made in the same year are also fretted type, but all of them have the compass of C to g'''.  There are no stabilizing braces on the baseboard. which are often seen in similar type of instruments.

Unfretted Clavichord   

Compass：　FF-f'''

Size：1355mmW x 479mmD x 145mmH
Reference： Drawing by Thomas F.H. Mace, 1978. Nuremberg: Germanisches Nationalmuseum. No. MIR 1061

Model：　Johann Heinrich Silbermann 1775

Key touch:
To play a clavichord, a player is required to hold the strings after the tangent hits the strings. The elastic key touch to further hold the strings, after the sound released, is the source of musical expressions specific to clavichords in addition to controlling the speed to tangents.

In the sharp keys, due to short distance between the balance pin and the key front, the key lever acts as a hard lever. For example, with the same string tension and the same striking point, a player needs stronger finger pressure to hold the strings for sharp keys than those for natural keys.

In a fretted clavichord, for example, c and c# share the same pare of strings. The c# striking point is closer to the center of the string and the force necessary to hold the string at the tangent is smaller than that for c. In a fortunate case, this soft force at the tangent is combined with the hard lever of c#, the finger pressure necessary to hold the c# string can be well balanced with the force for c. However, in the case of b♭(e♭) and b (e), the unbalance is magnified.

Individually balance the key touch can be assumed to be one of the advantages of unfretted clavichords, then considering this advantage, a proper string gauge selection was applied. The key touch is determined with following three parameters namely, string tension, striking point and key lever. Respecting the original design for striking point and key lay out, it was tried to select the proper string gauges in order to realize smooth changes in the key hardness. In the beginning, the string gauges were selected to provide smooth changes in the string tension over the whole range of the compass. However, a significant difference in key hardness between low-mid range and high range was found. Then, string gauges were reselected to provide smooth change in the key hardness. As a result, string tension for mid-low range was increased from 7Kg to 9Kg. In the highest one octave, one size thinner strings are used for notes assigned to sharp keys to obtain smooth changes in the key touch.

Compass：　FF-g'''

Size：1540mmW x 480mmD x 116mmH
Reference： Drawing by John Koster

Model：　Johann Christoph Georg Schiedmayer 1796