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The string instruments are those in which the sound is produced by the vibration of one or several of its strings.

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The vibration can be produced by various procedures.

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Rubbing the strings.

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Pressing them.

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Or hitting them.

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Piano

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The main percussive string instrument is the piano.

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Like the harpsichord, it has a series of strings inside a large piece of furniture that acts as a resonance box.

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The strings are not played directly, but through a keyboard.

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The interpreter, when pressing the keys, acts as a mechanism by which a small felt hammer

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strikes the strings, causing their vibration and, therefore, the sound.

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Each key acts as a single hammer, and each hammer strikes from one to three strings.

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The lowest notes only need a long and thick string.

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The low register notes are produced by the percussion of two strings,

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and the others by three simultaneous strings.

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The reason for this difference is to achieve a homogeneous intensity in all registers.

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Piano

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When a key is pressed, in addition to causing the hammer to strike certain strings,

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a felt switch is also removed, which, on the contrary, would prevent the string from vibrating freely.

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This switch remains inactive while the key remains pressed.

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At the moment when the key returns to its normal position,

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the switch moves towards the string, turning off the vibration and, therefore, the sound.

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The piano keyboard consists of 88 keys,

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and is the instrument that can produce the largest number of notes, from the very low to the very high.

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Piano

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The piano also has two frequent-use pedals that modify its sound.

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The right pedal releases the oppressive action of all the switches on all the strings,

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so that they can continue vibrating freely, even if the fingers do not remain pressing the keys.

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Piano

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Piano

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The left pedal deflects the trajectory of the hammers, which hit the strings more weakly.

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Piano

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Piano

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Piano

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Piano

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The piano, in short, is a very complete instrument, which can offer all kinds of intensities,

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because the strength of the sound depends directly on the impulse we give to the hammer,

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and this also depends directly on the force with which we hit the key.

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Piano

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Piano

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Piano

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Piano

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When the orchestra intervenes, it is placed behind the second violins, next to the harps.

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It is the instrument for which more works have been written in the last two centuries.

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Piano

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Piano

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Piano

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Piano

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Piano

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Piano