Piano

A piano is a keyboard instrument that produces sound when its keys are pressed, activating an action mechanism where hammers strike strings. Modern pianos have a row of 88 black and white keys—with the exception of the Bosendörfer and Stuart & Sons pianos—and tuned to a chromatic scale in equal temperament. A musician who specializes in piano is called a pianist.

There are two main types of piano: the grand piano and the upright piano. The grand piano offers better sound and more precise key control, making it the preferred choice when space and budget allow. The grand piano is also considered a necessity in venues hosting skilled pianists. The upright piano is more commonly used because of its smaller size and lower cost.

When a key is depressed, the strings inside are struck by felt-coated wooden hammers. The vibrations are transmitted through a bridge to a soundboard that amplifies the sound by coupling the acoustic energy to the air. When the key is released, a damper stops the string's vibration, ending the sound. Most notes have three strings, except for the bass, which graduates from one to two. Notes can be sustained when the keys are released by the use of pedals at the base of the instrument, which lift the dampers off the strings. The sustain pedal allows pianists to connect and overlay sound, and achieve expressive and colorful sonority.

History

The piano was based on earlier technological innovations in struck-string instruments and keyboard instruments. The earliest known keyboard instrument was the Ancient Greek hydraulis, a type of pipe organ invented in the third century BC. Pipe organs continued to be used in Europe through the middle ages, and as such the development of pipe organs enabled instrument builders to learn about creating keyboard mechanisms for sounding pitches. The first string instruments with struck strings were the hammered dulcimers, which originated in the Middle East and were introduced in Europe in the Middle ages. During the Middle Ages, there were several attempts at creating stringed keyboard instruments with struck strings. By the 17th century, the mechanisms of keyboard instruments such as the clavichord and the harpsichord were well developed. In a clavichord the strings are struck by tangents, while in a harpsichord they are mechanically plucked by quills when the performer depresses the key. Centuries of work on the mechanism of the harpsichord in particular had shown instrument builders the most effective ways to construct the case, soundboard, bridge, and mechanical action for a keyboard intended to sound strings.

The English word piano is a shortened form of the Italian pianoforte, derived from gravecembalo col piano e forte ("harpsichord with soft and loud"). Variations in volume (loudness) are produced in response to the pianist's touch (pressure on the keys): the greater the pressure, the greater the force of the hammer hitting the strings and the louder the sound produced and the stronger the attack. Invented in 1700, the fortepiano was the second keyboard instrument (the first being the clavichord) to allow gradations of volume and tone according to how forcefully or softly the player presses or strikes the keys, unlike the pipe organ and harpsichord.

Invention

The invention of the piano is credited to Bartolomeo Cristofori of Padua, Italy, who was employed by Ferdinando de' Medici, Grand Prince of Tuscany, as the Keeper of the Instruments. Cristofori was an expert harpsichord maker and was well acquainted with the body of knowledge on stringed keyboard instruments. This knowledge of keyboard mechanisms and actions helped him to develop the first pianos. It is not known when Cristofori first built a piano. An inventory made by his employers, the Medici family, indicates the existence of a piano by 1700. The three Cristofori pianos that survive today date from the 1720s. Cristofori named the instrument un cimbalo di cipresso di piano e forte ("a keyboard of cypress with soft and loud"), abbreviated over time as pianoforte, fortepiano, and later reduced to only piano.

Cristofori's great success was designing a stringed keyboard instrument in which the notes are struck by a hammer. The hammer must strike the string but not remain in contact with it, because continued contact would damp the sound and stop the string from vibrating and making sound. This means that after striking the string, the hammer must quickly fall from (or rebound from) the strings. The hammer must return to its rest position without bouncing violently, thus preventing notes from being re-played by accidental rebound. It must return to a position in which it is ready to play again almost immediately after its key is depressed, so the player can repeat the same note rapidly when desired. Cristofori's piano action was a model for the many approaches to piano actions that followed in the next century.

Early fortepiano

Cristofori's new instrument remained relatively unknown until an Italian writer, Scipione Maffei, wrote an enthusiastic article about it in 1711, including a diagram of the mechanism, that was translated into German and widely distributed. Most of the next generation of piano builders started their work based on reading this article. One of these builders was Gottfried Silbermann, better known as an organ builder. Silbermann's pianos were virtual copies of Cristofori's, with one important addition: Silbermann invented the forerunner of the modern sustain pedal, which lifts all the dampers from the strings simultaneously. This innovation allows the pianist to sustain the notes that they have depressed even after their fingers are no longer pressing down the keys. As such, by holding a chord with the sustain pedal, pianists can relocate their hands to a different register of the keyboard in preparation for a subsequent section.

Silbermann showed Johann Sebastian Bach one of his early instruments in the 1730s, but Bach did not like the instrument at that time, saying that the higher notes were too soft to allow a full dynamic range. Although this earned him some animosity from Silbermann, the criticism was apparently heeded. Bach did approve of a later instrument he saw in 1747 and even served as an agent in selling Silbermann's pianos. "Instrument: piano et forte genandt"—a reference to the instrument's ability to play soft and loud—was an expression that Bach used to help sell the instrument when he was acting as Silbermann's agent in 1749.

Piano making flourished during the late 18th century in the Viennese school, which included Johann Andreas Stein (who worked in Augsburg, Germany) and the Viennese makers Nannette Streicher (daughter of Stein) and Anton Walter. Viennese-style pianos were built with wood frames, two strings per note, and leather-covered hammers. Some of these Viennese pianos had the opposite coloring of modern-day pianos; the natural keys were black and the accidental keys white. It was for such instruments that Wolfgang Amadeus Mozart composed his concertos and sonatas, and replicas of them are built in the 21st century for use in authentic-instrument performance of his music. The pianos of Mozart's day had a softer tone than modern pianos (those from the late 19th century or later) or English pianos, with less sustaining power. The term fortepiano now distinguishes these early instruments (and modern re-creations) from later pianos.

Further developments

In the period from about 1790 to 1860, the Mozart-era piano underwent significant changes that led to the modern structure of the instrument. This revolution was in response to a preference by composers and pianists for a more powerful, sustained piano sound, which was made possible by the ongoing Industrial Revolution with resources such as high-quality piano wire for strings and precision casting for the production of massive iron frames that could withstand the tremendous tension of the strings. Over time, the tonal range of the piano was also increased from the five octaves of Mozart's day to the seven octave (or more) range found on today's pianos.

Early technological progress in the late 18th century owed much to the firm of Broadwood. John Broadwood joined with another Scot, Robert Stodart, and a Dutchman, Americus Backers, to design a piano in the harpsichord case—the origin of the "grand". This was achieved by about 1777. They quickly gained a reputation for the splendour and powerful tone of their instruments, with Broadwood constructing pianos that were progressively larger, louder, and more robustly constructed.

They sent pianos to both Joseph Haydn and Ludwig van Beethoven, and were the first firm to build pianos with a range of more than five octaves: five octaves and a fifth during the 1790s, six octaves by 1810 (Beethoven used the extra notes in his later works), and seven octaves by 1820. The Viennese makers similarly followed these trends. The two schools used different piano actions: Broadwoods used a more robust action, whereas Viennese instruments were more sensitive.

By the 1820s, the center of piano innovation had shifted to Paris, where the Pleyel firm manufactured pianos used by Frédéric Chopin, and the Érard firm manufactured those used by Franz Liszt. In 1821, Sébastien Érard invented the double escapement action, which incorporated a repetition lever (also called the balancier) that permitted repeating a note even if the key had not return to its resting position. This facilitated rapid playing of repeated notes, a musical device exploited by Liszt. When the invention became public, as revised by Henri Herz, the double escapement action gradually became standard in grand pianos and is still incorporated into all grand pianos currently produced in the 2000s.

Variations in shape and design

Some early pianos had shapes and designs that are no longer in use. The square piano, not truly square, but rectangular, was cross strung at an extremely acute angle above the hammers, with the keyboard set along the long side. This design is attributed to Christian Ernst Friderici, a pupil of Gottfried Silbermann, in Germany and Johannes Zumpe in England, and it was improved by changes first introduced by Guillaume-Lebrecht Petzold in France and Alpheus Babcock in the United States.

Square pianos were built in great numbers until the 1840s in Europe and the 1890s in the United States, and saw the most visible change of any type of piano: the iron-framed, over-strung squares manufactured by Steinway & Sons were more than two-and-a-half times the size of Zumpe's wood-framed instruments from a century before. Their overwhelming popularity was the result of inexpensive construction and price, although their tone and performance were limited by narrow soundboards, simple actions and string spacing that made proper hammer alignment difficult.

Types

Modern pianos have two basic configurations, the grand piano and the upright piano, with various styles of each. There are also specialized and novelty pianos, electric pianos based on electromechanical designs, electronic pianos that synthesize piano-like tones using oscillators, and digital pianos using digital samples of acoustic piano sounds.