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[Fr., It., Sp.; Eng. also pianoforte; Ger. also Klavier, Hammerklavier, Rus., Pol. fortepiano; fr. It. pianoforte or fortepiano, soft-loud, loud-soft].
A large stringed keyboard instrument. Its keyboard is a set of wooden levers attached to the action, which together operate a system of hammers. The player’s fingers press the keys, which move the action levers, driving the hammers to strike tuned strings stretched over one or more wooden bridges glued to a large wooden plate, the *soundboard. The strings vibrate at pretuned pitches. The bridge conveys the vibrations to the soundboard, which amplifies them by the vibration of its entire expanse.

Fig. 1. A photo of a Bösendorfer grand piano and a photo of an upright piano.

Modem pianos come in two shapes, the grand and the upright. In the wing-shaped grand piano [Fr. piano a queue, Ger. Fliigel, It. pianoforte a coda, Sp. piano de cola], the strings and soundboard are contained in a horizontal case, and the hammers strike the strings from below [Fig. 2], The wider keyboard end is about 1.4-1.5 m (4 ft. 7 in. to 4 ft. 11 in.) with the standard musical range of seven and one-third octaves (88 keys), A, to c"'" (some have ranges up to 8 octaves, C2 to c'"", with correspondingly greater widths). The length varies from under 1.5 m (4 ft. 11 in.) for a “baby” grand to about 2.75 m (9 ft.) for a standard concert grand (2.9 m., or 9 ft. 6 in., for eight-octave instruments—one manufacturer makes a grand of 3.1 m, or 10 ft. 2 in.). Upright pianos have the same standard range (a few are smaller), but the action must suit the vertical arrangement of strings, soundboard, and case. The upright action is a more complex mechanical problem than the grand’s. Uprights range from spinets, less than 1 m in height (36-38 in.—few are now being made) to larger consoles, studios, and uprights, about 1 m (3 ft. 5 in.) to 1.3 m (4 ft. 4 in.) in height.

Fig. 2. Cross section of modem grand piano action.
1. Keybed. 2. Keyframe. 3. Front rail. 4. Balance rail. 5. Balance rail stud. 6. Back rail.
7. Key stop rail. 8. White key. 9. Key covering. 10. Black key. 11. Key button.
12. Back Check. 13. Underlever key cushion. 14. Action hanger. 15. Support rail.

16. Support. 17. Fly. 18. Support top flange. 19. Balancer. 20. Repetition spring.
21. Hammer rest. 
22. Regulating rail. 23. Hammer rail. 24. Hammer shank.
25. Hammer. 26. Underlever frame. 
27. Underlever. 28. Damper stop rail.
29. Damper wire. 30. Damper guide rail. 31. Damper head. 
32. Damper felts.
33. String. 34. Tuning pin. 35. Sostenuto rod. (Courtesy of Steinway & Sons)

The piano’s capacity to vary the volume of its tones depends on the fact that the hammers are not pushed against the strings but are flung in free flight and bounce away. The hammer’s speed toward the string determines the volume of sound. In a well-regulated
action, the weight of the player’s finger on the key is precisely proportional to the loudness of the sound. The action’s leverage ratio allows a relatively light touch to produce the sound, usually between 45 and 55 grams (1.45 to 1.77 ounces). The key’s movement raises a damper from the string, which falls back on the key’s release.


Piano tone is expected to be rich and mellow but clear, with well-defined attack and adequate sustaining. Tone quality depends on several factors, principally the material and hardness of the hammers and the quality and design of the stringing. Well into the 19th century, wooden hammers were covered in leather, ordinarily deerskin. Other coverings were occasionally tried, but during the 1820s Henri Pape’s experiments introduced felt as an adequate alternative to leather. Leather hardens and cracks over time and must be replaced. Repeated blows against strings compact felt and groove it, necessitating reshaping and loosening. The harder the hammer’s material, the more strident the tone becomes. If it is too soft, the tone is ill-defined and “fuzzy.”

String tone is determined by the combination of pitch, duration, and timbre. Pitch is preestablished by the length of the string, the tension with which it is struck, and its mass. The shorter the string, the higher its tension, and the smaller its diameter, the higher the pitch. None of these qualities can be altered during playing. Duration, or sustain, depends principally on the tension of the wire, and the cast-iron frame on which the strings are stretched allows high tension. The tone of loosely stretched wire “decays” (fades away) quickly.

Timbre, “tone quality” itself, is a function of the kinds of vibration the string undergoes. A string vibrates in a number of modes simultaneously. It vibrates as a whole at the rate of its fundamental pitch, but it also vibrates in segments: halves, which give a pitch an octave above the fundamental; thirds, sounding a fifth higher than that; quarters, an octave above the half; fifths, a major third above the quarter, and so on. Acoustical science calls these higher tones overtones or harmonics, but on a piano they are best called partials. The pitches of the partials, theoretically infinite in number, form part of what we hear when a note is played, and the relative strengths among them are the major determinative of tone quality. If the highest partials are relatively too strong, the sound is hard and strident, if relatively too weak, the sound is dull and hollow.

The violinist or flutist can modify pitch with finger or mouth, but keyboard-instrument players cannot alter pitches during playing. In addition, the scales and musical keys used in Western music have some mathematical peculiarities that prevent all the *intervals in pianos from being pure. Tuners work to produce somewhat out-of-tune intervals that are acceptable to the ear. This is temperament, and it has various types. Early keyboards were tuned mostly in “mean-tone” temperaments, where keys with up to about three sharps or flats were nicely in tune and the others sounded more or less sour. Most familiar today is “equal temperament,” in which the 12 notes of the chromatic scale are tuned in a constant ratio to one another. Before equal temperament became the norm, “well temperaments” allowed more pleasing tuning for more keys than mean-tone temperaments, but some keys remained slightly jarring. J. S. Bach’s Well-Tempered Clavier probably assumed not equal temperament but well temperaments of various kinds. In any case, it is ironically the fact that well-tuned pianos are inevitably out of tune to an extent that only well-trained ears can hear.

Fig. 3. Cross section of typical modem grand piano. Early instruments are similar but lack the iron frame. (Action details are shown in Fig. 2.)
Key (1) propels hammer (2) to string (3) and lifts damper (4) via action mechanism (5). Vibrations of string, stretched from tuning pin (6) to hitch pin (7), pass via bridge (8) into soundboard (9). Iron frame (10) carries tension of strings, positioning pin block (11), and rim of wooden frame and case (12).

The piano began its career in a Medici palace in Florence, where Bartolomeo Cristofori (1655-1732) was harpsichord maker to Ferdinando (1663-1713), prince of Tuscany. In 1700 an inventory of Ferdinando’s musical instruments described “An arpicimbalo of Bartolomeo Cristofori, of new invention, which produces soft [It. piano] and loud [It. forte].” The description mentions “hammers, which produce the soft and loud,” making it clear that the arpicimbalo was a piano. Earlier stringed keyboard instruments with hammers did not succeed. Cristofori can, therefore, be designated—as he designated himself—the piano’s inventor. Various names for the instrument boiled down to pianoforte or fortepiano (now conventionally an instrument from the early 19th century or before), and they were ultimately shortened to piano.

Cristofori made harpsichords and clavichords, and we cannot know his motivation to design the hammer-driven piano. He claimed to have done it without help from anyone. His piano looked like a harpsichord, but it embodied the completely new principle of tone production, in which the hammer was propelled in free flight to the string. Scipione Maffei (1675-1755) described and praised the instrument’s qualities and gave a somewhat crude action diagram in an Italian journal in 1711. The actions in the three surviving Cristofori pianos (1720, Metropolitan Museum, New York; 1722, National Museum of Musical Instruments, Rome; 1726, Musical Instrument Museum, University of Leipzig, Germany) are wonders of mechanical design. Cristofori modified several parts of the instrument from the usual harpsichord construction: strings were heavier, the harpsichord jacks were altered to become the dampers, and several new aspects of bracing were introduced, because the hammer blows put more strain on the entire mechanism. Cristofori brilliantly solved all the problems of a hammer-action stringed keyboard instrument except one: a way to raise all the dampers at once. But the music of the time neither expected nor needed a solution to that problem. In 1732, the year of Cristofori’s death, Lodovico Giustini (1685-1743) published the first music specifically for the “harpsichord with soft and loud,” 12 sonatas dedicated to the prince of Portugal.

During the 1720s, Cristofori pianos came to the royal court of Portugal, where Domenico Scarlatti (1685-1757) certainly knew them, and, with the removal of Princess Maria Barbara to Spain in about 1730, Madrid came to know them. In 1725, Maffei’s article was translated in Germany, and Gottfried Silbermann (1683-1753), a Dresden instrument maker, succeeded by the 1740s in making pianos. He must have studied a Cristofori instrument, as his actions, like those of early pianos from strong Spanish and Portuguese traditions, are exactly like the actions in Cristofori pianos.

Grand piano by Louis Bas of  Villeneuve-lès-Avignon, France, 1781.
Earliest French grand piano known to survive; includes an inverted wrestplank and action derived from the work of Bartolomeo Cristofori
(ca. 1700)  with ornately decorated soundboard.

Others claimed invention. In 1716, Jean Marius’s (d. 1720) designs for “mallet harpsichords” submitted to the French Royal Academy of Sciences were approved, though he made no instruments. Christoph Gottlieb Schroter (1699-1782) submitted action designs to the elector of Saxony in 1721, expecting that an instrument would be built. It never happened, and Schroter later claimed that Silbermann stole his idea.

Both Marius and Schroter heard Pantaleon Heben-streit (1669-1750), a popular virtuoso on a huge *hammer dulcimer [Ger. Hackbrett]. Hebenstreit played expressively, with swells and diminuendos, and achieved an impressive wash of sound with his undamped strings. The instrument came to be named “pantalon.” Sometime during the 1720s, people thought of attaching a keyboard to the pantalon, and in 1731, Wahl Friedrich Fickem (or Ficker, fl. 1730s) announced in Leipzig the Clavir-Cymbal, which he claimed had the musical attributes of Hebenstreit’s instrument. Keyboard pantalons were much easier to play than the Hackbrett. They usually had bare wood or horn hammers, sometimes a second set of cloth- or leather-covered hammers, and hand-stops to moderate the bright, hard tone. Many were shaped like clavichords. A number of instruments thought to be square pianos of the middle to late 18th century are actually pantalons. It was a type of piano, with a hammer action and usually metal strings, but its aesthetic was different from that tracing to Cristofori.

The latter 18th century saw many square (actually rectangular) pianos derived partly from the clavichord, typically with a five-octave range, tiny leather hammers, and somewhat rudimentary actions, but, like pantalons, with hand-operated damper stops and other ways of softening or shortening the tone. These instruments were probably invented by 1766 by Johannes Zumpe (1726-90), a German immigrant to London, who became rich making squares, many of which survive. Intended mainly for the drawing rooms of wealthy homes, the piano was still an upper-class artifact.

Fig. 4. Early piano replica by the modern builder Paul McNulty, after Walter & Sohn, 1805

The growing interest of professional musicians in the piano led to its increasingly displacing the harpsichord as the preferred stringed keyboard instrument for public performance. The earliest known public performance was by Johann Baptist Schmid (dates unknown) in 1763 in Vienna. Two types of wing-shaped pianos (first called grand in an English patent, 1777) came to predominate, one mainly in England and France, the other in Austria and Germany. Their principal difference lay in the actions and in the stringing. The action diagrams [see A, B, C in Fig. 5] demonstrate the designs. The Continental (usually called Viennese) is much the lighter of the two and most unlike the Cristofori action. The English design, perhaps derived from Silbermann’s version of Cristofori’s action, is heavier, with a deeper dip of the key.

Fig. 5. Piano actions. In these simplified drawings, moving parts are shown in outline; shaded areas are fixed members; solid black is cloth, felt, or leather.

A: English grand action.
(1) string; (2) damper;

(3) balance rail; (4) pin block. When key is pressed, jack (5) drives hammer (6) until disengaged near end of stroke by set-off button (7). Hammer fall is stopped by back check (8), raised by key motion. When key is released, hammer falls and jack reengages notch.   

Viennese action:
(1) damper; (2) balance rail; (3) pink block. Key raises hammer (4) via pivot in fork or Kapsel (5). Beak (7) slips free of overhang on hopper (6) just before hammer strikes string.
C: Head of hammer falls, stopping on back check (8), having shifted left while pivoting about balance point at (2). On release, beak reengages hopper (6); hammer head is freed and falls to rest (9).

The English grands typically had three strings for each note, where the German and Austrian ones had only two. The sound of the English pianos was bigger and often coarser than the small, clear sound of the German instruments. Mozart (1765-91) was the foremost exponent of the German-type grand, which had been designed first by Johann Andreas Stein (1728-92) in Augsburg. Mozart wrote to his father from Augsburg in 1777 praising Stein’s pianos. Stein’s children, Matthaus Andreas (1776-1842) and Nannette Stein Streicher (1769-1833), became influential piano makers in Vienna, along with Anton Walter (1752-1826), one of whose pianos Mozart owned (still in the Mo-zarteum in Salzburg). The pianist-composer Muzio Clementi (1752-1832), later a piano maker in London, was the major influence on players of the English grand, demanding techniques appropriate to its heavier action and larger sound. John Broadwood (1732-1812) founded an enormously successful company and dominated the English and French market.

As the 19th century opened, two other shapes of pianos were emerging, both vertical. “Pyramid” pianos, tall, symmetrical instruments known from the mid-18th century, gave way in England to tall, rectangular instruments, grand pianos standing upright and occupying wall space instead of floor space. In Germany and Austria the favored tall upright was the “giraffe,” whose case shape followed that of the grand, with a curved side. About 1800 Matthias Muller (c. 1770-1844) in Germany and John Isaac Hawkins (1772-1855) in the U.S. simultaneously designed small uprights, barely 1.4-1.55 m(4 ft. 6 in. to 5 ft. 1 in.) high, but neither influenced others. Shorter uprights began to appear around 1810-15, especially those of Robert Womum (1780-1852), whose “cottage pianos” with a newly designed action facilitated the piano’s move to more modest homes. As the Industrial Revolution gathered momentum, a middle class acquiring cultural aspirations was a ripe market for the instrument. Though the square continued until about 1860 in Europe and until the turn of the 20th century in America, increasingly the upright displaced it in most homes. The growing piano industry trained most of its energies on instruments for the home, though the 19th century also saw a burgeoning of public concerts, new and larger concert halls, and more and more trained pianists. The result was new developments in the grand.

Prime among them, affecting also squares and verticals, was growth. Cristofori’s instruments had four octaves; by Mozart’s time the range was five octaves, F1-ff". During the 1790s, ranges were widening to c"", and by 1810 the six octaves from F1-f'" (especially in Germany and Austria) and C1-c"" (especially in England and France) were coming into use. The next decade saw extensions from C1-f"", and in the 1820s, a very few seven-octave pianos, A2-a"", though that range was becoming standard only at the middle of the century, and instruments with smaller ranges continued to be made. Five-octave squares were made in America into the 1830s. The main period of the extending range, 1790-1825, coincides with the career of Beethoven (1770-1827) and can be traced through his piano music; the “Hammerklavier” Sonata, op. 106, reaches the C1-f"" compass.

As grands grew, problems with existing actions were exacerbated. In 1821 the Parisian maker Se-bastien Erard (1752-1831) patented his “repetition” or “double escapement” action, designed so that the player could repeat a note without completely releasing the key [see Fig. 5 D, E]. Though other action designs continually appeared, and English and Viennese types continued in use until the early 20th century, Erard’s eventually won the day and has come to be used in nearly all contemporary grands.

Fig. 5. Piano actions.

Erard/modem action.
D: Key at rest. Repetition lever (1) and jack (2) pivot on carrier (3); whole assembly pivots at (4). Jack passes through a rectangular hole in repetition lever (shown cut away). Springs at (5) bear clockwise on (1) and (2). When carrier (3) is slightly raised, repetition lever (1), supported by spring, lifts hammer via roller (6). After partial stroke, left end of repetition lever is stopped; continuing stroke carries jack and carrier upward, compressing spring and lifting right end off position stop at (4). Jack rises until arm is stopped at (7), which snaps other end clear of roller (6) just before note sounds.
E: When hammer falls as key is held, roller contacts repetition lever. With sufficient momentum on strongly played notes, hammer will force repetition lever down against spring, and hammer head will be caught by back check (8). Slight key release lets jack reengage roller; back check releases hammer. Repetition is now possible from a range of release depths: quicker from partial release, most powerful from full release.

The piano’s growth necessitated an increase in strength. With more and heavier strings, wooden bracing proved inadequate: many fine pianos warped alarmingly, and others collapsed. Wooden braces also exacerbated the fact that humidity changes, making wood shrink or swell, caused pianos to lose their tuning. In the 18th century, English makers had introduced iron braces between the pin block and the belly rail (which supports the front of the soundboard). In 1820, James Thom (fl. 1820s) and William Allen (fl. 1820-40?), working for William Stodart (1762?-ca. 1838) in London, invented a “compensation frame.” Tubes of brass and iron, corresponding to brass and iron strings, extended lengthwise in the case and would theoretically expand and contract with temperature changes at the same rate as the strings. Partial frames with metal hitch-pin plates and bars above the strings, bolted into the pin block, were the main solution from the 1820s. In 1825, Alpheus Babcock (1785-1842) in Boston patented a single-piece metal frame for squares. A few American makers adopted it in the 1830s, and Jonas Chickering (1798-1853) of Boston patented it for grands in 1843. This proved the lasting solution both to tuning stability and to the increasing demand for greater volume necessitated by larger concert halls. Its combination in 1859, by Henry Steinway, Jr. (1830-65), with cross-stringing in grands in effect brought the modem piano into being. Cross-stringing (or overstringing) runs the longest bass strings above and across the plane of the tenor strings, allowing for the longest strings possible in the case (an advantage for tone), and had been used sometimes in squares and very small uprights since Henri Pape (1789-1875) invented the design in 1828.

By the middle of the 19th century, the piano industry had largely changed from craft-shop technology to factory technology, with workers performing specialized operations and an increasing use of machines for planing, sawing, and some making of parts. Specialist companies making only actions or cases or keys proliferated in both Europe and America, and some makers became assemblers of parts rather than manufacturers. Production increased rapidly, especially in North America, and export trade began from Europe and America. In America, the opening of the West with railroad transport encouraged an increase in the sale of pianos and the number of manufacturers. The piano had long been an icon of high culture, but as prices fell, it came within the means of even very modest homes, especially as purchase on credit came to be more common.

Since the late 18th century, companies like Broad-wood in England and Erard in France had dominated the trade in their countries. Others had come to the fore, notably Chickering in the U.S. A series of world’s fairs during the 19th century, beginning with
the Crystal Palace exhibition in London in 1851, demonstrated advances in technology and the arts, affording piano makers opportunities to compete and gain reputation. At the fair in Paris in 1867, Steinway & Sons and Chickering gave a boost to the American industry by winning the first prizes. The Germans, with such makers as Bechstein, Bltithner, Schiedmayer, Grotrian, and others, came to dominate the European market. French and English makers, who had led the way in the earlier 19th century, relied on older technologies and fell back from leadership. By the beginning of the 20th century the modem piano had definitively appeared, with cross-stringing and iron frames, steel strings, and the Erard grand action, and the upright had displaced the square in homes everywhere.

The 20th century saw many experiments but little lasting technological change. New materials included resin glues and plastics after World War II. Automation entered piano factories, more in some than in others. Yamaha in Japan led the way, but by no means have all manufacturers followed, nor is Yamaha completely automated. Some important experiments began in the late 1800s. Paul von Janko (1856-1939) invented a keyboard in which parallel rows of whole-tone keys allow wide stretches and simplified fingering. Emanuel Moor (1863-1931) devised a two-manual piano that allowed simplified playing of octaves, and some concave keyboards were tried. Pianos were designed for quarter tones and for the microtonal scales from 1/3 to 1/16 tones devised by Julian Carillo (1875-1965). That for 1/16 tones required 97 keys to cover one octave.

Electric piano

Most successful were automatic pianos and electric and electronic instruments. Pneumatic player pianos used air or vacuum pressure to run perforated paper rolls on which the music was programmed. E. S. Votey (1856-1931) patented the Pianola, one of the earliest and most successful brands, in 1900. “Piano players” [Ger. Vorsetzer] sat in front of an ordinary piano and mechanical fingers touched the keys. “Player pianos” had the mechanism inside the case. Expressive factors such as tempo change and loudness were accomplished by hand-operated levers. More sophisticated “reproducing pianos” recorded actual performers’ playing on rolls, with expressive values accomplished automatically. For several years in the 1920s, more automatic pianos were manufactured than ordinary pianos. Electric pianos were relatively shortlived. An early One, the Neo-Bechstein, invented in the 1930s, had no soundboard, but groups of strings converged on electromagnetic pickups connected to an amplifier. Some electric pianos were devised after World War II, most successfully the Fender-Rhodes, invented by Harold Rhodes (1910-2000). Electronic keyboards, now collectively called keyboards, have multiple sounds, including several different piano sounds, programmed on computer chips. Early synthesizers attempted unsuccessfully to imitate piano sound, but keyboards use “sampling,” which extends a somewhat simplified recorded piano sound to the entire keyboard. Keyboards, having no strings, are not pianos. The sounds of the best are plausible accounts of the piano, and the keys are weighted to simulate the touch of good pianos. Their flexibility of use recommends them to composers and popular musicians. Whether they will actually displace pianos, as the piano displaced the harpsichord, is not clear.

The center of gravity of the piano industry has moved since about 1970 to Asia, where Japan became the largest producer, Yamaha the largest maker. Korea soon followed suit (Young Chang, Samick), and China’s piano industry is expanding (Pearl River, Dongbei). Many old brands are now made in Asia: Knabe and Weber by Young Chang, Kohler & Campbell by Samick, Schiedmayer by Kawai (Japan), and many others. This Asian activity has certainly energized the European and American industries.

Edvard Grieg. Piano Concerto in A Minor

Celebrating Chopin's life and music a fantasy painted in 1840 by Joseph Danhauser with Franz Liszt on piano and listening novelists George Sand and Alexandre Dumas, Hector Berlioz, Giochino Rissini, Niccolo Paganini with a bust of Beethoven the the piano

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