What makes keys so important?
A pianist would first judge a piano by its action and then by its own sound. All dynamics, phrases and colors are interpreted through a simple key which really is only a slow-fast and soft-loud switch. This is why piano is a difficult instrument as these are the only expressive tools the pianist has in contrast with other string instruments that exhibit a huge color palette: soft-hard, vibrato-straight, pizzicato, harmonics, glissando and so on.
What makes piano unique, is that it is a machine and a musical instrument together, like a car and an engine. The piano builder is called to manage both the skills of an engineer and a luthier together and piano evaluation involves both the front (action) and the back (musical instrument). A fine high end piano must prove excellence in both. However, in a real word when this is not the case, the pianist would go for the excellent key and action rather than the sound. This does make sense considering that the key is responsible for the energy transfer in an extremely complex key movement that would look so simple otherwise. It works almost as it was originally designed by Erard, almost 200 years ago employing over 9000 moving parts…
Therefore key performance does not improve by employing some super action design but through quality parts, the right geometry, proper fitting and mostly understanding the interaction of all the action systems. We give seminars on action evaluation to bring pianists closer to their instrument and piano buyers to a more efficient decision. We explain how the same parts and assembly methods can lead to a mediocre piano or to a superb piano.
This text is too small to tackle a huge and very serious aspect of piano making, not only due to its complexity but also due to its undercover secret knowledge. Time and again we face a locked box of secrets in piano building. There is no book on how to make a piano, how to design it, why it works that way. We are called to experiment, research old aged fine pianos, meet people that do the same and also hope for some good luck not to get lost on the way.
A superb action “matches” the hammers and action parts to the string scale- bearing- crown- soundboard system. Fine keys and actions give freedom to the artist’s hands. No effort to tame the piano but instead all energy is deployed on interpretation.