Anatomy of a Grand Piano

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What makes a grand piano grand?

Widely considered the pinnacle of achievement for musical instruments, grand pianos of any size – from baby grand pianos all the way to concert grand pianos – produce an unparalleled and distinct sound. But what contributes to such a signature musical capability?grand piano parts 35831 300x271 - Anatomy of a Grand Piano

The Rim – The Grand Piano’s Shape and Size

Made from spruce or maple in the finest pianos, the rim is the piece that gives the grand piano its distinct shape. The unique acoustic environment, size of the body, and length of the strings produce a signature sound in grand pianos. If string material and tension are similar between two pianos, the grand piano with longer strings will have less inharmonicity – which means that the overtones sound less sharp relative the same note in a different octave. In pianos with shorter strings, like many cheaper upright pianos, the octaves need to be stretched – tuning to the lower octave’s sharper overtones instead of to the true octave. The more perceptible the inharmonicity, the harsher the note from the piano.

The lid, when held at its open angle, directs the sound outward and upward, increasing the apparent volume of the sound, and allowing the music to fill the room. You may have noticed that in nearly every concert, the grand piano’s lid is opened toward the audience – the redirected sound being warmer and more audible the audience this way.


The Cast Iron Plate

Also called ‘the harp’ the plate is the real structure of the piano. Constructed from cast iron because its used to hold over 18 tons of string tension. Cheaply made plates can have bubbles form in the cast iron, causing the piano to have an unpleasant ring, which will interrupt the tonal purity of the grand piano. Properly constructed plates often uses sand casting, which helps to mitigate, and in many cases entirely remove, the bubbles formed during casting.

The Tuning Pins and the Pinblock

The pinblock is the primary board against which the strings are anchored, using rotating tuning pins to change the pitch of each individual string. Tuning pins are one of the two main pin anchors. Made from laminated pieces of the hardest woods, the pin block is put under huge strain due to the immense tension of the strings. As a piano ages and is poorly cared for the setting holes for the pins may become oversized requiring a new pin block or the use of new, larger tuning pins. The quality of your pinblock is one of the things that will dictate how frequently you need to tune your piano.

The Soundboard

The other component used to direct sound, the soundboard is a thin sheet of wood the size and shape of the whole piano. This directs the omnidirectional sound from the vibrating strings up and out of the belly of the grand piano. Often made by laminating many boards of softer wood together, the soundboard is used to amplify the sound from the piano. The soundboard may also have ribs running in the opposite direction of the grain and seams of the wood used in its construction.

The Bridges

The treble and bass bridges are affixed to the sound board, and are made of a much harder wood than the soundboard to prevent the string tension from warping or delaminating the bridges. In addition to the bridges holding the strings in place, tuning pins and hitch pins are used to anchor the strings, in addition to felts and hammers guiding the strings.01 20 200x300 - Anatomy of a Grand Piano

The Strings

Mostly made from high carbon spring steel for its high fatigue resistance, tensile strength and vibration retention. Also called piano wire, these strings find uses in many other devices for precisely these reasons, finding their way into surgical devices, springs, construction and model planes and trains. All wire used in professional grand pianos need to have less than an 8 micrometers (millionths of a meter) variation, or roughly 1/20th the width of a human hair’s variation, or the string will produce false tones.

There are an enormous variety of strings, some are bound in different metals or cushioned with different materials. Some pianos are even double or triple strung to produce a variety of timbres.

The Keys and The Action

Every time a key is depressed the complex grand piano action is put into motion, resulting in the hammer striking the taught string, in turn giving us the beautiful sound. Unlike upright pianos, grand pianos use gravity to reset their keys, which also means that they’re slightly faster to reset than upright pianos. Made of over 30 constituent parts, the actions of pianos, both upright and grand pianos, are extremely complex, spring loaded mechanisms that need to be reliable and durable. These complex machines are present in the early models of grand pianos, and still function as designed 100+ years later. Here’s an excellent breakdown of the grand piano’s action.

Grand Pianos For Sale

We pride ourselves on having the largest selection of new and used grand pianos for sale in the Atlanta, GA area – we also ship nationwide! From beautiful, late 19th century Austrian grand pianos, like Bosendorfer pianos, to modern Yamaha uprights and baby grands. Our grand pianos for sale are kept in immaculate condition and refurbished to produce beautiful music and true tones. If you have any questions or you want to purchase a grand piano for your home please call us at (770) 717 8047. Or come visit our showroom or huge warehouse – we’re stocked to the brim with grand pianos for sale and we will be happy to help in any way that we can, just let us know!

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