Listen to the Piano: click link below

The piano is by-in-large the most highly demanded and frequently played instrument in the world. Even entering the fourth century of its existence, the piano still maintains its supremacy in the music world. It’s complexity reigns true and with each development since its invention, it continues to provide increased levels of nuanced expression, duration of tone, and delicate volume. The piano is a complex assembly of felt coverings, wooden hammers, metal springs, giant soundboard, and a structure that can support twenty tons of string tension! But, this instrument hasn’t been around forever and has undergone years of improvements and changes.
The piano, like most other inventions, did not come without its predecessors. The keyboard’s layout and our twelve-tone system came way before the piano. Keyboard instruments include the clavichord and harpsichord. The clavichord is probably the closest relative to the piano. It involves a similar hammer system including a tangent that strikes strings and remains in contact with them, sort of like a fret. The problem, though, is that the dynamic expression is quite limited, ranging only up to the mezzo-piano level. The harpsichord, which dates back to 1505, was also a very popular keyboard instrument before the piano. The harpsichord, like a harp, creates its sound by having plectra pluck the strings. Volume can be adjusted mechanically by adjusting the length of the plectrum. The harpsichord is very limited, though, as the dynamics are almost a nonentity and the player’s “touch” has no weight upon how loud the instrument sounds.
Bartolomeo Cristofori was a harpsichord maker and keeper of instruments for the Medici court. It was around 1700 that he produced the “gravicembalo col piano e forte.” This instrument was the first successful attempt at producing a keyboard instrument with hammers to hit the strings. The instrument worked with a small roll of parchment and leather fitted atop a wood molding and an “escapement” design. This design allowed the hammer to be thrown at the string freely and then escape rather than stay against the string. This allowed for free vibration of the string.
Throughout the 18th century and onward to the early 19th century the piano underwent evolution. Yet, not until Sebastian Erard did the piano undergo a serious change. It was in 1821 the Erard invented the “double escapement” idea. This invention made it possible for a hammer to hit the string twice before returning back to its original position, allowing rapid repetition of notes to be possible. With Liszt and Chopin writing for the piano, makers were continually trying to increase the volume of the piano. Strings become heavier and more tense. Iron bars were added to the timbers of the cases and the piano became ever-increasingly louder.
In 1825, an American piano maker Alpheus Babcock patented his invention of a full cast iron plate, which removed the tension from the wooden case. After this invention, innovations started coming in droves. Jonas Chickering developed Babcock’s idea and fitted a grand piano with a full iron frame. Eventually, the piano evolved to the 88-keyed grand pianos we know of today. Since 1885, the piano has stayed relatively stagnant until the player piano of the 1890s. 
Since then, the 20th and 21st century have showed us the introduction of electronics and digital interface. In the 60s, many electric pianos came into play, using the same hammer and string idea but with electric pickups similar to an electric guitar. The turn of the 21st century has shown us a myriad of new digital technologies. Companies have created so many synthesized sounds that it’s hard to keep up.