The FORTEPIANO played in most of the recordings presented, was built between 1815 / 20 in Vienna by Benignus Seidner. You can find a similar instrument, by the same manufacturer, in the Schubertmuseum of Vienna.
Unlike modern instruments, this grand Fortepiano doesn't have a cast-iron frame and is built entirely of wood. The absence of iron support limits the tension of the strings, which are consequently very little strained; the strings are rather thin. Its soundboard has a thickness of only about four millimetres, those of modern instruments measure between eight to ten millimetres. Its hammers weigh only one or two grams each; their heads are covered with leather, unlike the actuel felt-covered hammers, which weigh eight to ten grams each. It has a range of six octaves. The instrument's different timbres are obtained by four pedals, from the left to the right: |
Shifting action: sideway shift of the keyboard whereby the hammers strike only one or two strings.
Bassoon stop: a bar covered with paper descends to the strings of the three lowest octaves and produces a droning sound when it vibrates. Moderator: a strip of felt is inserted between the hammers and strings, this of course changes the sound. Lifting of the dampers: allowing harmonics to vibrate, which enriches the sound. |
The FORTEPIANO used for Mozart works is a copy by Paul McNulty of an instrument by Anton Walter (1795). It has a range of five octaves. The instrument's different timbres are obtained by three pedals, from the left to the right: |
Shifting action: sideway shift of the keyboard whereby the hammers strike only one or two strings.
Moderator. Lifting of the dampers. |
Conclusion: the characteristic sound of the Fortepiano is produced chiefly by the leather covered hammers and the lower tension of the strings.
tleonhar@hispeed.ch |