Grand Pianos (三角钢琴）
The vast majority of grand pianos sold today are equipped with three piano pedals. For the most part, those three pedals have the same function from piano to piano.
What Does the Right Pedal on a Piano Do?
The pedal on the right is referred to as the the Damper Pedal (制音踏板) or the Sustain Pedal (延音踏板) because when you press this pedal with your right foot, all of the felt dampers raise up and the strings are free to vibrate and sustain as long as those dampers are raised. When single notes are played on a grand piano, as soon as the finger comes off the note, the notes immediately stop ringing. This is because as soon as the key is let go of, the damper comes back down and silences the string. When the damper pedal is engaged however, all of the strings are free to ring out even after your finger has left the key.
What Does the Middle Pedal on a Piano Do?
The middle pedal on a Grand Piano is referred to as the Sostenuto Pedal ( * 保持音踏板、持续音踏板或保留音踏板). Interestingly, very few players actually make use of this pedal because it produces a highly specific effect that is only called for in select classical works. The middle pedal functions by allowing the player to sustain specific notes, with the other notes operating as normal with the dampers depressed. There’s some romantic sheet music that calls for the use of this pedal, along with works by composers such as Claude Debussy and Maurice Ravel that make use of this pedal. But for the most part in mainstream piano playing the sostenuto pedal is a seldom-used feature.
What Does the Left Pedal on a Piano Do?
The left pedal on a grand is called the Una Corda Pedal (弱音踏板), and actually moves the entire keyboard and hammers to the right. When it’s set up correctly, the hammers move enough to the right that the treble hammers only strike two strings instead of three, thereby reducing the total sound output and also changing the timbre slightly. This is probably the most misunderstood of the three pedals, but it’s use is actually called for fairly often in classical music.
* Upright Piano - 立式钢琴上，左踏板也被称作弱音踏板、柔音踏板