This article is about the modern musical instrument. For other meanings, see piano (disambiguation).
A piano is a large musical instrument with a keyboard. Its sound is produced by strings stretched on a rigid frame. These vibrate when struck by felt-covered hammers, which are activated by the keyboard.
The word piano is an abbreviation for pianoforte, Italian for soft-loud, referring to the ability of the piano to play notes at different volumes depending on how hard its keys are pressed. The name pianoforte is now applied to an older, more lightly built pattern of piano.
As a keyboard stringed instrument, the piano is similar to the clavichord and harpsichord. The three instruments differ in the mechanism of sound production. In a harpsichord, strings are plucked by quills or similar material. In the clavichord, strings are struck by tangents which remain in contact with the string. In a piano, the strings are struck by hammers which immediately rebound, leaving the string to vibrate freely. The hammered dulcimer is loosely related in that it has no keyboard, but has strings that vibrate when struck with a (handheld) hammer.
The piano has been a crucial instrument in the tradition of Western classical music. A large number of composers were also pianists, and they frequently used the piano as a tool for composition.
A person who performs music on the piano is a pianist.
The piano was invented by Bartolomeo Cristofori in Florence, Italy. When he built his first piano is not entirely clear, but Franceso Mannucci wrote in his diary that Cristofori was working on an "arcicembal che fa il piano e il forte" ("harpsichord that plays both softly and loudly") as early as 1698. All of his surviving instruments date from the 1720s. Cristofori built only about 20 pianofortes before he died at age 75 in 1731, roughly 21 years after he invented the first pianoforte.
The piano was founded on earlier technological innovations. In particular, it benefited from centuries of work on the harpsichord, which had shown the most effective ways to construct the case, the soundboard, the bridge, and the keyboard. Cristofori was himself a harpsichord maker and well acquainted with this body of knowledge.
Cristofori's great success was to solve, without any prior example, the fundamental mechanical problem of piano design: the hammers must strike the string but not continue to touch it once they have struck (which would damp the sound). Moreover, the hammers must return to their rest position without bouncing violently, and it must be possible to repeat a note rapidly. Cristofori's piano action served as a model for the many different approaches to piano actions that were to follow.
Cristofori's early instruments were made with thin clavichord strings and were much quieter than the modern piano. However, they could produce a wider range of dynamics than the clavichord, and the sound sustained longer.
Cristofori's new instrument remained relatively unknown until an Italian writer, Scipione Maffei , wrote an enthusiastic article about it, complete with diagrams of the mechanism. This article was widely distributed, and most of the next generation of piano builders started their work as a result of reading it.
One of these builders was Gottfried Silbermann , better known as an organ builder. Silbermann's pianos were virtually direct copies of Cristofori's, but with an important exception: Silbermann invented the forerunner of the modern damper pedal, which permits the dampers to be lifted from all the strings at once. In Cristofori's pianos, this was done not by depressing a pedal, but by pulling on an organ-style draw-stop. Virtually all subsequent pianos incorporated some version of Silbermann's idea.
Silbermann showed Bach one of his early instruments in the 1730s. Bach did not like it at that time, claiming that the higher notes were too soft to allow a full dynamic range. Though this earned him some animosity from Silbermann, the latter did apparently heed the criticism. Bach did approve of a later instrument he saw in 1747, and apparently even served as an agent to help sell Silbermann's pianos.
Piano-making flourished during the late 18th century in the work of the Viennese school, which including Johann Andreas Stein (who worked in Augsburg, Germany) and the Viennese makers Nannette Stein (daughter of Johann Andreas) and Anton Walter . The Viennese-style pianos were built with wooden frames, two strings per note, and leather-covered hammers. It was for such instruments that Mozart composed his concertos and sonatas, and replicas of them are built today for use in authentic-instrument performance. The piano of Mozart's day had a softer, clearer tone than today's pianos, with less sustaining power. The word "tinkling" is unfair when applied to the lovely sound of these instruments, but it does perhaps suffice to convey roughly how they differ in tone from modern pianos.
The term fortepiano is often used to distinguish the 18th-century style of instrument from later pianos.
In the lengthy period lasting from about 1790 to 1890, the Mozart-era piano underwent tremendous changes which ultimately led to the modern form of the instrument. This evolution was in response to a consistent preference by composers and pianists for a more powerful, sustained piano sound. It was also a response to the ongoing Industrial Revolution, which made available technological resources like high-quality steel for strings and precision casting for the production of iron frames.
Over time, piano playing became a more strenuous and muscle-taxing activity, as the force needed to depress the keys, as well as the length of key travel, was increased. The tonal range of the piano was also increased, from the five octaves of Mozart's day to the 7 1/3 (or even more) octaves found on modern pianos.
In the first part of this era, technological progress owed much to the English firm of Broadwood , which already had a strong reputation for the splendor and powerful tone of its harpsichords. Over time, the Broadwood instruments grew progressively larger, louder, and more robustly constructed. The Broadwood firm, which sent pianos to both Haydn and Beethoven, was the first to build pianos with range of more than five octaves: five octaves and a fifth during the 1790s, six by 1810 (in time for Beethoven to use the extra notes in his later works), and seven by 1820. The Viennese makers followed these trends. The two schools, however, used different piano actions: the Broadwood one more robust, the Viennese more sensitive.
By the 1820s, the center of innovation had shifted to the Érard firm of Paris, which built pianos used by Chopin and Liszt. In 1821, Sébastien Érard invented the double escapement action, which permitted a note to be repeated even if the key had not yet risen to its maximum vertical position, a great benefit for rapid playing. As revised by Henri Herz about 1840, the double escapement action ultimately became the standard action for grand pianos, used by all manufacturers.
Some other important technical innovations of this era include the following:
- use of three strings rather than two for all but the lower notes
- the iron frame. The iron frame, also called the "plate", sits atop the soundboard, and serves as the primary bulwark against the force of string tension. The iron frame was the ultimate solution to the problem of structural integrity as the strings were gradually made thicker, tenser, and more numerous (in a modern grand the total string tension can approach 20 tons). The iron frame was invented in 1825 in Boston by Alpheus Babcock , culminating an earlier trend to use ever more iron parts to reinforce the piano. The first iron frame in grand pianos (1840) was the work of the Chickering firm, at which Babcock was employed.
felt hammers. The harder, tauter steel strings required a softer hammer type to maintain good tone quality. Hammers covered with compressed felt were introduced by the Parisian maker Jean-Henri Pape in 1826, and are now universally used.
- the sostenuto pedal (see below), invented in 1844 by Jean Louis Boisselot and improved by the Steinway firm in 1874.
- the overstrung scale, also called "cross-stringing". This is a special arrangement of strings within the case: the strings are placed in a vertically overlapping slanted arrangement, with two bridges on the soundboard instead of just one. The purpose of the overstrung scale was to permit longer strings to fit within the case of the piano. Overstringing was invented by Jean-Henri Pape during the 1820s, and first applied to the grand by Henry Steinway Jr. in 1859.
Duplex scaling: Treble strings of a 182 cm. grand piano. From lower left to upper right: dampers, main sounding length of strings, treble bridge, duplex string length, duplex bridge (long bar perpendicular to strings), hitchpins.
duplex scaling, invented by Theodore Steinway in 1872, permits the parts of the string near its ends, which otherwise would be damped with cloth, to vibrate freely, thus increasing resonance and adding to the richness of the sound. Aliquot stringing, which serves a similar purpose in Blüthner pianos, was invented by Julius Blüthner in 1873.
The modern concert grand achieved essentially its present form around the beginning of the 20th century, and progress since then has been only incremental.
Some early pianos had shapes and designs that are no longer in use. The once-popular square piano had the strings and frame on a horizontal plane, but running across the length of the keyboard rather than away from it. It was similar to the upright piano in its mechanism. Square pianos were produced through the early 20th century; the tone they produced is widely considered to be inferior. Most had a wood frame, though later designs incorporated increasing amounts of iron. The giraffe piano, by contrast, was mechanically like a grand piano, but the strings ran vertically up from the keyboard rather than horizontally away from it, making it a very tall instrument. These were uncommon.
Piano history and musical performance
The huge changes in the evolution of the piano have somewhat vexing consequences for musical performance. The problem is that much of the most widely admired music for piano—for example, that of Haydn, Mozart, and Beethoven was composed for a type of instrument that is rather different from the modern instruments on which this music is normally performed today (for example, tuning for A was set to 422 Hz). Even the music of the early Romantics, such as Chopin and Schumann, was written for pianos substantially different from ours.
One view that is sometimes taken is that these composers were dissatisfied with their pianos, and in fact were writing visionary "music of the future" with a more robust sound in mind. This view is perhaps more plausible in the case of Beethoven, who composed at the beginning of the era of piano growth, than it is in the case of Haydn or Mozart.
Others have noted that the music itself often seems to require the resources of the early piano. For example, Beethoven sometimes wrote long passages in which he directs the player to keep the damper pedal down throughout (a famous example occurs in the last movement of the "Waldstein" sonata , Op. 53). These come out rather blurred on a modern piano if played as written but work well on (restored or replicated) pianos of Beethoven's day. Similarly, the classical composers sometimes would write passages in which a lower violin line accompanies a higher piano line in parallel; this was a reasonable thing to do at a time when piano tone was more penetrating than violin tone; today it is the reverse.
Current performance practice is a mix. A few pianists simply ignore the problem; others modify their playing style to help compensate for the difference in instruments, for example by using less pedal. Finally, participants in the authentic performance movement have constructed new copies of the old instruments and used them in performance; this has provided important new insights and interpretations of the music.
The modern piano
Types of piano
Modern pianos come in two basic configurations and several sizes: the grand piano and the upright piano.
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 large amount of space and needs a spacious room with high ceilings for proper resonance. Several sizes of grand piano exist. Manufacturers and models vary, but as a rough guide we can distinguish the "concert grand", approx. 3 m; the "grand", approx. 1.8 m; and the smaller "baby grand", which may be a bit shorter than it is wide. All else being equal, longer pianos have better sound, so that full-size grands are almost always used for public concerts, whereas baby grands are only for domestic use where space and cost are crucial considerations.
Upright pianos, also called vertical pianos, are more compact because the frame and strings are placed vertically, extending in both directions from the keyboard and hammers. It is considered harder to produce a sensitive piano action when the hammers move sideways, rather than upward against gravity; however, the very best upright pianos now approach the level of grand pianos of the same size in tone quality and responsiveness. For recent advances, see Innovations in the piano.
In 1863, Henri Fourneaux invented the player piano, a kind of piano which "plays itself" from a piano roll without the need for a pianist. Also in the 19th century, toy pianos began to be manufactured.
A relatively recent development is the prepared piano, which is a piano adapted in some way by placing objects inside the instrument, or changing its mechanism in some way.
Since the 1990s, digital pianos have been available, which digitize the sound of each piano note. Digital pianos have become quite sophisticated, with standard pedals, weighted keys, multiple voices, MIDI interfaces, and so on in the better models. However, with current technology, it remains difficult to duplicate a crucial aspect of acoustic pianos, namely that when the damper pedal (see below) is depressed, the strings not struck vibrate sympathetically with the struck strings. Since this sympathetic vibration is considered central to a beautiful piano tone, digital pianos are still not considered by most experts as competing with the best acoustic pianos in tone quality. Progress is now being made in this area by including physical models of sympathetic vibration in the synthesis software.
Keyboard and pedals
Almost every modern piano has 88 keys (seven octaves and a bit, from A0 to C7). Many older pianos only have 85 (from A0 to A6), while some manufacturers extend the range further in one or both directions. The most notable example of an extended range can be found on Bösendorfer pianos, some of which extend the normal range downwards to F, with others going as far as a bottom C, making a full eight octave range. On some models these extra keys are hidden under a small hinged lid, which can be flipped down to cover the keys and avoid visual disorientation in a pianist unfamiliar with the extended keyboard; on others, the colours of the extra keys are reversed (black instead of white and vice versa) for the same reason. The extra keys are added primarily for increased resonance; that is, they vibrate sympathetically with other strings whenever the damper pedal is depressed and thus give a fuller tone. Only a very small number of works composed for piano actually use these notes. More recently, the Stuart and Sons company has also manufactured extended-range pianos. On their instruments, the range is extended up the treble for a full eight octaves. The extra keys are the same as the other keys in appearance.
For the arrangement of the keys on a piano keyboard, see Musical keyboard. This arrangement was inherited from the harpsichord without change, with the trivial exception of the color scheme (white for naturals and black for sharps) which became standard for pianos in the late 18th century.
Pianos have had pedals, or some close equivalent, since the earliest days. (In the 18th century, some pianos used levers pressed upward by the player's knee instead of pedals.) The three pedals that have become more or less standard on the modern piano are the following.
The damper pedal is often simply called "the pedal," since it is the most frequently used. It is placed as the rightmost pedal in the group. Every note on the piano except for (approximately ) the top two octaves is equipped with a damper, which is a padded device that prevents the strings from vibrating. The damper is raised off the strings of its note whenever the key for that note is pressed. When the damper pedal is pressed, all the dampers on the piano are lifted at once, so that every string can vibrate. This serves two purposes. First, it permits notes to be connected (i.e., played legato) when there is no fingering that would make this possible. More important, raising the damper pedal causes all the strings to vibrate sympathetically with whatever notes are being played, which greatly enriches the tone.
Piano music starting with Chopin tends to be heavily pedaled, as a means of achieving a singing tone. In contrast, the damper pedal was used only sparingly by the composers of the 18th century, including Haydn, Mozart and Beethoven; in that era, pedaling was considered primarily as a special coloristic effect.
The soft pedal or "una corda" pedal is placed leftmost in the row of pedals. On a grand piano, this pedal shifts the action to one side slightly, so that hammers that normally strike all three of the strings for a note strike only two of them. This softens the note and also modifies its tone quality. For notation of the soft pedal in printed music, see Italian musical terms.
The soft pedal was invented by Cristofori and thus appeared on the very earliest pianos. In the 18th and early 19th centuries, the soft pedal was more effective than today, since it was possible at that time to use it to strike three, two or even just one string per note—this is the origin of the name "una corda", Italian for "one string". In modern pianos, the strings are spaced too closely to permit a true "una corda" effect—if shifted far enough to strike just one string on one note, the hammers would also strike the string of the next note over.
On upright pianos, the soft pedal is replaced by a mechanism for moving the hammers' resting position closer to the strings. This reduces volume, but does not change tone quality as a true "una corda" pedal does.
The sostenuto pedal or "middle pedal" maintains in the raised position any damper that was raised at the moment the pedal was depressed. It makes it possible to sustain some notes (depress the sostenuto pedal before releasing the notes to be sustained) while the player's hands have moved on to play other notes, which can be useful for musical passages with pedal points and other tricky situations. The sostenuto pedal was the last of the three pedals to be added to the standard piano, and to this day many cheap pianos—and even a few good ones—do not have a sostenuto pedal. (Almost all modern grand pianos have a sostenuto; most upright pianos do not.) A number of twentieth-century works call for the use of this pedal.
Some upright pianos have a practice pedal in place of the sostenuto. This pedal, which can usually be locked in place by depressing it and pushing it to one side, drops a strip of felt between the hammers and the keys so that all the notes are greatly muted—a handy feature for those who wish to practice at odd hours without disturbing others in the house. The practice pedal is rarely used in performance.
The materials of the piano
Many parts of a piano are made of materials selected for extreme sturdiness. In quality pianos, the outer rim of the piano is made of a hardwood, normally maple or beech. According to Harold A. Conklin, the purpose of a sturdy rim is so that "the vibrational energy will stay as much as possible in the soundboard instead of dissipating uselessly in the case parts, which are inefficient radiators of sound." The rim is normally made by laminating flexible strips of hardwood to the desired shape, a system that was developed by Theodore Steinway in 1880.
The thick wooden braces at the bottom (grands) or back (uprights) of the piano are not as acoustically important as the rim, and are often made of a softwood, even in top-quality pianos, in order to save weight.
The pinblock, which holds the tuning pins in place, is another area of the piano where toughness is important. It is made of hardwood, and generally is laminated (built of multiple layers) for additional strength and gripping power.
Piano strings (also called piano wire), which must endure years of extreme tension and hard blows, are made of high quality steel. They are manufactured to vary as little as possible in diameter, since all deviations from uniformity introduce tonal distortion. The bass strings of a piano are made of a steel core wrapped with copper wire, to increase their flexibility. For the acoustic reasons behind this, see Piano acoustics.
The plate, or metal frame, of a piano is usually made of cast iron. It is advantageous for the plate to be quite massive. Since the strings are attached to the plate at one end, any vibrations transmitted to the plate will result in loss of energy to the desired (efficient) channel of sound transmission, namely the bridge and the soundboard. Some manufacturers now use cast steel in their plates, for greater strength. The casting of the plate is a delicate art, since the dimensions are crucial and the iron shrinks by about one percent during cooling. The inclusion in a piano of an extremely large piece of metal is potentially an esthetic handicap. Piano makers overcome this handicap by polishing, painting, and decorating the plate; often plates include the manufacturer's ornamental medallion and can be strikingly attractive.
The numerous parts of a piano action are generally hardwood or plastic. The choice between these two materials is controversial. Some varieties of plastic, incorporated into pianos in the 1950's and 1960's, were clearly disastrous, crystallizing and losing their strength after one or two decades of use. The Steinway firm once used Teflon, a plastic, for some action parts, but ultimately abandoned the experiment. More recently, the Kawai firm has built pianos with action parts made of more modern and effective plastics; these parts have held up better and have generally received the respect of piano technicians.
View from below of a 182-cm grand piano. In order of distance from viewer: softwood braces, tapered soundboard ribs, soundboard. The metal rod at lower right is a humidity control device.
The part of the piano where materials probably matter more than anywhere else is the soundboard. In quality pianos this is made of solid spruce (that is, spruce boards glued together at their edges). Spruce is chosen for its high ratio of strength to weight. The best piano makers use close-grained, quarter-sawn, defect-free spruce, and make sure that it has been carefully dried over a long period of time before making it into soundboards. In cheap pianos, the soundboard is often laminated; i.e. made of plywood.
Piano keys are generally made of spruce or basswood, for lightness. Spruce is normally used in high-quality pianos. Traditionally, the white keys were covered with strips of ivory, but since ivory-yielding species are now endangered and protected by treaty, plastic is now universally used. The Yamaha firm innovated a plastic, since imitated by other makers, that mimics the feel of ivory on the player's fingers.
The requirement of structural strength, fulfilled with stout hardwood and thick metal, makes pianos heavy. Even a small upright can weigh 300 pounds (136 kg), and the Steinway concert grand (Model D) weighs 990 pounds (480 kg). The largest piano built, the Fazioli F308, weighs 1520 pounds (691 kg).
Care and maintenance of pianos
- Main article: Care and maintenance of pianos
Pianos are regularly tuned to keep them up to pitch and produce a pleasing sound. Less often, their hammers are voiced to compensate for gradual hardening. Top-quality but aged pianos can be restored, replacing a great number of their parts to produce an instrument closely similar to a new one.
Famous piano makers
The Piano Book by Larry Fine (4th ed. Jamaica Plain, MA: Brookside Press, 2001; ISBN 1-929145-01-2) gives the basics of how pianos work, and a thorough evaluative survey of current pianos and their manufacturers. It also includes advice on buying and owning pianos.
- The pianist's guide to pedaling by Joseph Banowetz (Bloomington : Indiana University Press, 1985) offers a history of the three piano pedals and covers the wide variety of ways in which they are used by professional pianists.