A piano contains several thousand parts. To understand how a piano works, though, you need only understand how six basic parts act together to produce sound. These basic parts of a piano are the:
- Key
- Action
- Hammer
- Damper lever
- Damper
- String
How the Pieces Fit Together
Each key on a piano is several times longer than it appears on the keyboard: it extends inside the piano where it connects to an action. An action is a system of levers that holds, at its end, a felt-covered mallet called a hammer.
The key extends beyond its point of connection to the action, finally ending below a lever called the damper lever. The damper lever, in turn, is connected to another felt-covered pad called a damper. When a key has not been pressed, the damper rests against a steel string that’s stretched taut right above the hammer.
Each key has its own action, hammer, damper lever, damper, and string.
What Happens When You Press a Piano Key
When you press a piano key, three things happen:
- The damper rises: The back end of the key pushes upward against the damper lever, which in turn lifts the damper off the string.
- The hammer strikes: The system of levers that make up the action causes the hammer to shoot upward and strike the string. After striking the string, the hammer falls away so that it no longer touches the string. The harder the player hits the key, the harder the hammer strikes the string, and the louder the resulting note sounds.
- The string vibrates: The strike from the hammer causes the string to vibrate. The vibrating string produces a sound with a fixed, specific pitch.
The precise note that a string produces depends on the length and width of the string.
- The longest, fattest strings: Produce the lowest, fullest-sounding notes and are located at the player’s extreme left (when seated at the keyboard)
- The shortest, thinnest strings: Produce the highest, thinnest-sounding notes and are located at the player’s extreme right (when seated at the keyboard)
What Happens When You Let Go of a Key
When you let go of a key, the key ceases to hold up the damper lever. The damper then moves down until it touches the string once more. The damper causes the string to stop vibrating and cuts off the note.
How Piano Tuners Work
Piano strings are in tune when they produce the proper note when played. To be in tune, each string must have a certain tension, which piano tuners can control by adjusting the piano’s tuning pins.
Foot Pedals
The piano contains three pedals that players operate with their feet. These pedals allow players to control the volume of notes and the length of time for which those notes sustain, or continue sounding.
- Damper pedal: When you press this rightmost foot pedal, all dampers lift from the strings. Any key you then play will sustain—rather than cut off—when released. Once you release the damper pedal, the dampers lower, muting all the strings.
- Sostenuto pedal: When you press this center foot pedal, any dampers that are already lifted by the player’s keystrokes remain in the “up” position. In a technique known as selective sustain, you can play certain keys while pressing the sostenuto pedal so those notes sustain, while playing other notes without pressing the pedal so those notes don’t sustain. Select-ive sustain is usually available only on grand pianos.
- Soft pedal: When you press this leftmost pedal, the volume of the sound produced by a depressed key softens. On grand pianos, the pedal impacts tone quality and volume; on uprights, it affects only volume.
