Piano terminology

General interest: see also:

Special interest:

The Harmonic Theory Home Page

The art of piano tuning

Six myths about piano tuning

What is the theory of piano tuning ?

The place of piano tuning theory

Why are pianos tuned to Equal Temperament and what is it?

What makes a piano string vibrate ?

On falseness and paradigms for the nature of piano tuning

On scales, tone, pitch (and piano tuning)

Books:

Theory and practice of piano tuning

BTEC Advanced Diploma in Piano Action Regulating

The traditional, full name of the instrument, derived from the Italian piano and forte, i.e. literally quiet and loud. After the gravicembalo col piano et forte invented by Cristofori (c. 1709), developed from the harpsichord. The modern instrument is substantially different in design and construction. Early pianos without iron frames are now conventionally referred to as fortepianos.

Grand piano sizes ranging from less than 5' in length to about 9' 6" in total length.

'sharps', 'raised' or 'black' keys, the full concert compass is 88 notes (7 1/4 octaves). (But some Bosendorfer grands, for example, have extra keys in the lower bass). 85 notes (7 octaves) is another standard also considered 'full compass'. Miniature instruments may have, for example, 6 octaves or 5 1/4 octaves.

This is the vertical board at the front, above the fall, covering the top half of the piano, that can be removed.

The removable 'door' at the bottom of an upright piano, underneath the keyboard.

The wooden (spruce) sound amplifying structure inside the piano, across which the strings are tensioned. The soundboard is a composite structure consisting of (usually) parallel grained planks of (usually) spruce, and "belly bars" which are strips of wood glued to the back of the soundboard, normally at right angles to the grain of the soundboard. The soundboard looks flat, but in fact forms a shallow three-dimensional arch, the curvature known as the soundboard's "crown" or "buck".

The bridges terminate the speaking lengths of the strings. There is a bridge at each end of the speaking length of the strings - one on the iron frame, and one on the soundboard. There are generally three or four bridges altogether, two on the soundboard and one or two on the iron frame. Sometimes on the iron frame there may be agraffes or studs instead, which are individual units, one per note, with holes through which the strings pass. Agraffes on the upright piano each have an individual bridge as part of the construction. The bridges on the iron frame, or agraffes or studs, provide a rigid boundary to one end of the string's speaking length. The soundboard bridges, i.e. the long bridge and the bass bridge, transmit the vibrating string's energy to the soundboard. On a grand piano the rigid bridge provided by the iron frame may be in the form of a capo d'astro, which bridges on top of the strings.

This is cast iron, usually gold painted. It takes the tension of the strings. It is very heavy, and needs to be, for acoustical reasons. Both old and new pianos are heavy. Hence, a heavy piano does not indicate it is an obsolete design - it is a feature of the best modern instruments.

The left pedal on a grand piano, and occasionally on an upright piano. The pedal shifts the whole action to one side so that the hammers strike only two out of three strings in the trichords, or one out of two in the bichords. Its use provides a better and more sustained tone, when playing quietly.

The left pedal on most modern upright pianos. Moves the hammer rest rail forward towards the strings so that the blow distance (the distance between the hammers and the strings) is reduced, thus reducing the power of the action by introducing lost motion, or reducing the depth of touch (how far the keys can be pressed down at the front). Occasionally found as the left pedal on small grand pianos.

The right pedal on all pianos. Lifts all the dampers simultaneously, causing notes to sustain and resonate.

Usually the middle pedal on a modern upright. Drops a strip of celeste felt between the hammers and the strings, to quieten the piano for practice without annoying the neighbors!

See Practice pedal. On older upright overdamper pianos, this may be the left pedal. A strip of celeste felt is brought up between the hammers and the strings, to quieten the piano.

The middle pedal on many grand pianos. Lifts the dampers of notes whose keys are already depressed, leaving the other dampers unaffected. Occasionally a middle pedal on a small grand piano is colloquially called the 'sostenuto' pedal, when in fact it lifts all the bass dampers simultaneously. Some upright pianos also have a genuine sostenuto pedal.

The (removable) mechanism for translating the movement of the keys to the movement of the hammers that strike the strings. Contains over 4000 parts.

The felt covered wooden 'hammers' that strike the strings, producing the sound. The felt is traditionally high quality Merino wool.

Soft, felt covered, wooden action components that are at rest in contact with the strings, stopping them sounding. As a key is depressed, the damper of that note is lifted off the string, allowing it to sound.

The wooden laminated plank into which the wrest pins (tuning pins) are inserted.

An international standard that sets A above middle C to a frequency of 440 cycles per second. Some orchestras prefer alternate pitches, usually slightly higher.

If the pitch of a piano drops by more than about six cycles per second below concert pitch, it is said to be below pitch.

If the piano is below pitch, bringing the instrument back to concert pitch is called a pitch raise. A pitch raise is a different kind of tuning, involving more work, than a normal tuning. In tuning terms, a semitone pitch drop is a large pitch drop.

The adjustment and setting of movements, distances, spring tensions, alignments, and timings, of the various parts of the action.

The touch of the action is its 'feel' and response in playing. The touch has two aspects - correctness of response, and weight of touch. Weight of touch has three components, all with different properties.

A single piano note comprises 1, 2 or 3 strings. Hence the term 'unison' may applied to the piano, may mean 'a group of three strings tuned to a musical unison'.

The bass strings cross over the plain steel strings, on a different plane. This allows longer strings, giving a better tone.

The modern type of upright piano action in which the dampers are beneath the hammers.

A now obsolete type of upright piano action in which the dampers are above the hammers.

The modern type of grand piano action. The roller itself is a leather covered component fixed to the underside of the hammer shank.

The modern type of grand piano action. The mechanism enables a repeat note to be played, with full control, after allowing the key to rise again only a minimal amount.

The normal mechanism of the upright piano action, and some obsolete types of grand piano action.

A mechanism by which the hammer is set free from the rest of the action pushing it towards the string, just before it strikes the string. This enables the hammer to bounce naturally off the string, rather than blocking against it.

The process of reducing tension in the hammer felts, or hardening the felt, to affect changes to the tone of the piano.

The system of stringing used on some Bluthner pianos in which over half or more of the compass, an extra, unstruck string is added to each note. This improves the tone and sustaining qualities of the instrument.

The system adopted in quality grand pianos (originally by Steinway), in which the part of the string between the long bridge and the hitch pin, where the string is anchored to the iron frame, passes over an additional bridge just in front of the hitch pin. This part of the string's length is allowed to vibrate, thus altering the response of the long bridge to vibrations from the main speaking length. The extra vibrating section has a length which is an harmonic proportion (a whole number fraction) of the main speaking length. This improves the tone and sustaining qualities of the piano.

Some very small grand pianos have two overstrung sections of bass strings. The highest covered bass strings cross over the tenor string section, and the lowest covered bass strings cross over these, on a higher, third plane.

The bass strings are usually covered in copper windings. These add mass to the strings without overly increasing the stiffness of the strings.

One end of each string is coiled around the tuning pin, which is turned in the tuning process. The tuning pins are inserted in the wrest plank or pin block

The music desk on a grand piano traditionally has larger flat areas on each side, that were originally used for candles, and hence are still sometimes referred to as candle boards.