Origin
The piano was invented by Bartolomeo Cristofori (1653 - 1731), a citizen of Padova, Italy, approximately in 1711. This instrument was called by its creator "gravicembalo col pian e forte" (kind of "harpsicord with piano and forte"), to emphasize its main ability: to produce sounds of different intensity.
Denomination
Piano belongs to the family of keyboard instruments; the sound is produced by hitting tight strings.
Sound generation
Before piano was invented, keyboard instruments (that is, belonging to the harpsichord family) were not able to play "piano" or "forte": their sound, in fact, has always the same intensity, apart from how strongly (or softly) we press the keys. This happens because these instruments produce their sound by plucking their strings with special devices called "salterelli".
Bartolomeo Cristofori overcame this expressive limitation by introducing three new devices:
- the hammers
- the escapement
- the damper
Let's see in detail how they work.
The hammers replace the salterelli and let the performer hit the string instead of plucking it.
The escapement is a device which makes the hammer come back into rest position immediately after it has hit the string; this behaviour is independent from the position of the key, that is, it happens even if the key is kept pressed. This way, the string is free to vibrate.
The damper is a small block of wood covered by felt: in rest position, it rests on the string, preventing it from vibrating. When the key is pressed, the damper rises and the hammer hits the string. Only when the key is released the damper falls on the string, stopping its vibration.