What Do Piano Pedals Do?

When you sit down at your piano, you might be focused solely on the keys in front of you. But if you’re not using any of the three pedals down near the floor, your music may not be as expressive as it could be. Incorporating your piano’s pedals can add depth and richness by changing the intensity, length, and quality of each note. 
There are only three pedals on your piano, but it’s not immediately obvious what each one does. Here’s how each one adds a unique dimension to your playing.

First, Understand How Pianos Work

Pianos are percussion instruments so intuitively, you might think this process is no more complicated than playing the drums. But in fact the hammer hits the string, immediately releases to allow the string to vibrate, and then a damper takes its place when you release the key. 
Check out this clip to see how it all comes together.
https://youtu.be/uBEL3YVzMwk?si=Qa5AsrPt0dQFmed4&t=84
This is how the piano action operates when you don’t use any of the pedals. Once you incorporate pedals, this process changes and allows the strings to vibrate differently.

Right Pedal (Sustain Pedal)

The pedal on your right will probably be the most useful to you, and its effects are the most obvious. When you press it down, it raises all the dampers, allowing the strings to vibrate freely, sustaining the notes as long as the pedal stays pressed.

Left Pedal (Soft Pedal)

The left pedal, or una corda, helps you play softer. “Una corda” means “one string” in Italian, and this is precisely what the left pedal does to your music. Instead of shifting the dampers, it moves the keys and the entire keybed slightly to the side. This subtle shift alters how the hammers strike the strings, causing them to hit fewer strings than usual, making your piano sound softer and more delicate.
In an upright piano, this process works a little differently. In this case, the left pedal moves all the hammers closer to the strings, reducing the force with which they strike. 

Center Pedal

The center pedal’s role depends on your piano’s style and model. Some pianos don’t have a center pedal at all.
  • Sostenuto Pedal: The center pedal is usually a sostenuto pedal. It’s similar to the right pedal, but it can sustain only the notes that were played before engaging the pedal, leaving all the other notes to sound as long as they are pressed.
  • Bass Sustain Pedal: This pedal acts like the right-side sustain pedal but exclusively sustains the lowest ¼ to ⅓ of strings, adding depth to the low end of your music.
  • Practice Mute: Need to keep the noise down during practice? Engage this function, and a cloth or felt strip lowers between the hammers and strings. The hammers contact this material first, so the volume is greatly reduced. If your piano’s middle pedal is a practice mute, the pedal may slide into an L-shaped slot that holds the pedal down as you play.
  • Second Soft Pedal: In some cases, it performs the exact same function as the left pedal, helping you play softly when needed.
  • Mandolin Attachment (Rinky-Tink): This feature is more often found in player pianos, but it could be retrofitted. The mandolin attachment lowers a series of riveted strips in front of the hammers This creates a tinny metallic sound that may remind you of a mandolin, or (more likely) a piano in a wild west saloon. 
  • Multiple Middle Pedals: I once came across an 1880s upright piano that had two center pedals. One pedal controlled the practice mute, and the other operated the rinky-tink.
  • Just for Show: I worked on a rare few pianos that had a central pedal that did nothing at all. But it looked good!

Highlight the Pedals’ Capabilities

Feeling inspired to make the most of your instrument’s abilities? Practice these well-known pieces that emphasize the pedals and see how much more dimension you can add to your playing.
  • “Moonlight Sonata” (Beethoven): This is an excellent example of how the right sustain pedal can add mood to your music. The first movement is particularly famous for its delicate opening notes, which are sustained throughout the piece.
  • Nocturnes (Chopin): Chopin’s Nocturnes make extensive use of the sustain pedal to blend notes, which adds a dreamy quality.
  • “Clair de Lune” (Debussy): This is a beautiful example of how the una corda pedal softens your piano’s sound to be more delicate and serene.
  • “Maple Leaf Rag” (Joplin): This tune is quintessential ragtime – a genre that plays well with a rinky-tink or old timey sound. If your piano happens to have the mandolin attachment, try this piece to showcase the effect.