Parts of a Piano


Almost every modern piano has 88 keys (seven octaves plus a minor third, from A0 to C8). Many older pianos only have 85 keys (seven octaves from A0 to A7), while some manufacturers extend the range further in one or both directions.

Some Bösendorfer pianos extend the normal range downwards to F0, with one other model going as far as a bottom C0, making a full eight octave range. Sometimes, 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, and on others, the colours of the extra white keys are reversed (black instead of white).

Piano parts - Piano pedal

The extra keys are added primarily for increased resonance from the associated strings; 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 both down the bass to F0 and up the treble to F8 for a full eight octaves. The extra keys are the same as the other keys in appearance.

Small studio upright type acoustical pianos with only 65 keys (which are called "gig" pianos) have been manufactured for use by roving pianists. Even though they contain a cast iron harp, they are comparatively light weight so they can be easily transported to and from engagements by only two men. Because their harp is longer than that of a spinet or console piano they have a stronger base sound which to some pianists is well worth the trade-off in range that a reduced key-set leaves them.


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.) Some cheaper instruments have only two pedals; but every piano has at least a damper pedal and a soft pedal. Most pianos with three pedals add the sostenuto pedal to that basic pair.

Damper pedal

The damper pedal (also called the sustain pedal or, erroneously, loud pedal) is often simply called "the pedal", since it is the most frequently used. It is placed as the rightmost pedal in the group. The mechanism for each note, except in the top two octaves, includes a damper, which is a pad that prevents the note’s strings from vibrating. Normally, the damper is raised off the strings whenever the key for that note is pressed. But when the damper pedal is depressed, all the dampers on the piano are lifted at once, so that all the strings in the instrument are free from contact with dampers. This serves two purposes. First, it assists the pianist in producing a legato (playing smoothly connected notes) in passages where there is fingering that will enable legato. Second, raising the dampers leaves all the strings free to vibrate sympathetically with whichever notes are being played, which greatly enriches the piano’s tone.

Sensitive pedaling is one of the techniques a pianist must master, since piano music from Chopin onwards tends to benefit from extensive use of the sustain pedal, both as a means of achieving a singing tone and as an aid to legato. In contrast, the sustain pedal was used only sparingly by the composers of the 18th century, including Haydn, Mozart, Beethoven in his early works; in that era, pedalling was considered primarily as a special coloristic effect.

Soft pedal

The soft pedal or "una corda" pedal is placed leftmost in the row of pedals. Soft pedals on some pianos are designed to lock in place, sustaining the effect without the musician applying constant pressure to the pedal. On a grand piano, this pedal shifts the whole action including the keyboard slightly to the right, so that hammers that normally strike all three of the strings for a note strike only two of them. This softens the note and modifies its tone quality. For notation of the soft pedal in printed music, see List of musical terminology.

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 pianos were manufactured with only two strings per note, and just one string per note would therefore be struck. This is the origin of the name "una corda", Italian for "one string". In modern pianos, there are three strings per note (except for lower notes, which have two, and the very lowest, which have only one). 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 hit the string of the next note.

On many upright pianos, the soft pedal instead operates a mechanism that moves the hammers’ resting position closer to the strings. Since the hammers have less distance to travel this reduces the speed at which they hit the strings, and hence the volume is reduced, but this does not change tone quality in the way the "una corda" pedal does on a grand piano. When this pedal is depressed on the vertical piano, it changes the action creating what is called "lost motion": that is, the jack is now further from the hammer butt, and now has to travel further to engage the hammer. This lost motion changes the touch and feel of the playing action, and as a result many pianists never use the soft pedal on a vertical piano. Some of the best old vertical pianos in the early 20th century used what is called a "lost motion compensator", a mechanism that would remove the lost motion when the soft pedal was depressed. Since the grand piano soft pedal simply shifts the action sideways, it does not change the touch and feel of the action, another advantage grand pianos have over vertical pianos.

Digital pianos often use this leftmost pedal to alter the sound to that of another instrument such as the organ, guitar, or harmonica. Pitch bends, Leslie speaker on and off, vibrato modulation, etc.

Sostenuto pedal

The sostenuto pedal or "middle pedal" keeps raised any damper that was already raised at the moment the pedal is depressed. This makes it possible to sustain some notes (by depressing the sostenuto pedal before notes to be sustained are released) while the player’s hands are free to play other notes. This can be useful for musical passages with pedal points and other otherwise tricky or impossible situations. The sostenuto pedal was the last of the three pedals to be added to the standard piano, and to this day many pianos are not equipped with a sostenuto pedal. Almost all modern grand pianos have a sostenuto pedal, while many upright pianos do not.

A number of 20th-century works specifically call for the use of the sostenuto pedal, for example Olivier Messiaen’s Catalogue d’oiseaux. This pedal is often unused in modern music.

Bass sustain pedal

On many vertical pianos, the middle pedal is merely a bass sustain pedal: that is, when it is depressed, the dampers lift off the strings only in the bass section. This pedal would be used only when a pianist needs to sustain a single bass note or chord over many measures, while playing the melody in the treble section. Given its limited use musically, few pianists even bother to use this pedal. Some grand pianos use this bass sustain type pedal rather than using a true sostenuto pedal, often an indication the grand piano was cheaply made (although some of the better old grand pianos also had this pedal).

Other kinds of pedal

Some vertical pianos have a practice pedal or celeste 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 strings so that all the notes are greatly muted — a handy feature for those who wish to practice in domestic surroundings without disturbing the neighbours. Such practice pedal is rarely used in performance, especially due to the nature of the felt swinging into place; a slow and somewhat stifled movement.

The rare transposing piano, of which Irving Berlin possessed an example, uses the middle pedal as a clutch which disengages the keyboard from the mechanism, enabling the keyboard to be moved to the left or right with a lever. The entire action of the piano is thus shifted to allow the pianist to play music written in one key so that it sounds in a different key.

The pedal piano is a rare type of piano that includes a pedalboard, enabling bass register notes to be played with the feet, as is standard on the organ. There are two types of pedal piano: the pedal board may be an integral part of the instrument, using the same strings and mechanism as the manual keyboard, or, less frequently, it may consist of two independent pianos (each with its separate mechanics and strings) which are placed one above the other, a regular piano played by the hands and a bass-register piano played by the feet.

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