Piano
Piano is a common abbreviation for pianoforte, a musical instrument with a keyboard. Sound is produced by strings stretched on an iron frame. These vibrate when struck by felt-covered hammers, which are activated by the keyboard.
It is said to have been invented by Bartolomeo Cristofori, who originally called it a "gravicembalo col piano e forte": a large harpsichord with soft and loud. "Pianoforte" stuck as the name for the instrument.
History
Early pianos had wooden frames, two strings per note, and deerskin-covered hammers. The development of the modern piano owes much to the collaboration between Beethoven and the English firm of Broadwood: as Beethoven grew progressively more deaf, the instruments that Broadwood sent him grew progressively larger, louder, and more robustly constructed -- iron frames, three strings per note, the modern felt-covered hammer.
Throughout the 19th century, Steinway patented many innovations on piano technology, notably the middle selective sustain pedal and advances in hammer action allowing cleaner repeated notes. Other manufacturers added features such as supplementary resonating strings, unstruck and undampened, which add harmonics to the sound.
The modern instrument
Pianos come in two basic types and several sizes:
Upright pianos are more compact due to the frame and strings being placed vertically, extending in both directions from the keyboard and hammers. The sound quality is adversely affected by several factors: firstly (the shortened distance the hammers travel -- need to check).
To fit in the full length of the bass strings, these are sharply angled diagonally across the body of the piano. This also affects sound quality as the hammers do not strike parallel to the string, and causes problems in tuning due to the stresses on the frame at the transition point between string groups. Furthermore, the left-hand pedal's una corda function -- which on grand pianos moves the entire action, thereby making the hammers strike one string instead of three -- isn't possible, because the differences in string angle would not allow a consistent reduction in tone quality ly across the range of notes. The workaround, moving the hammers' resting position close to the strings is reasonably effective in reducing volume, but the tone obtained is weak rather than expressive.
Grand pianos have the frame and strings placed horizontally, with the strings extending away from the keyboard. This avoids the problems inherent in an upright piano, but takes up a great deal more space. Several sizes of grand piano exist. Manufacturers may vary, but in general they are: "concert grand": approx. 3m; "grand": approx 1.8m; and "baby grand". The baby grand is designed for domestic use, although its much shortened strings mean the sound quality is poorer than an upright: a baby grand is not for musicians, rather people wishing to be seen to own a grand piano.
There are two other lesser seen kinds of piano: the square piano has the strings and frame on a horizontal plane, but running across the length of the keyboard rather than away from it. It is similar to the upright piano in its mecahnism. The giraffe piano, by contrast, is mechanically like the grand piano, but the strings run vertically up from the keyboard rather than horizontally away from it. This makes it a very tall instrument.
The average piano has 88 keys (7 octaves and a bit, A to C). Many older pianos only have 85 (from A to A), and some manufacturers (Bosendorfer), extend further in both directions.
The keys for a piano are white and black. The keys are ordered so the notes ascend in pitch, from left to right.
Typically piano music is written with a treble clef and a bass clef. Each group of 12 semitones is an octave (so called, because there are eight whole notes, or white keys per octave). There are five black notes for the half-steps within an octave.
The pattern for black and white keys is White-Black-White-Black-White-White-Black-White-Black-White-Black-White. (ie: C C# D D# E F F# G G# A A# B )
Much great music has been written for the piano, with it being an instrument central to the classical music repertoire.
A relatively recent development is the invention of the prepared piano, which is a piano adapted in some way by placing objects inside the instrument, or changing its mechanism in some way. John Cage is famous for his use of this instrument.
A person who plays a piano is known as a pianist.
Piano is also a dynamic direction in music, often appearing in sheet music as p, and indicating to the performer that he should play softly. It is the opposite of forte, meaning "loudly".