Soundboard
A wooden plate that amplifies string vibrations (piano, harp).
What it means
The soundboard is a thin wooden plate that takes up the vibrations of the strings and passes them on to the air as sound. A string alone sounds very quiet because it moves little air. The large soundboard takes over the vibration via the bridge and radiates it over a large surface, so that the tone becomes loud and full.
Musical use
In the piano and grand piano the soundboard is usually made of spruce and reinforced with ribs, which keep it stable and shape the sound. The harp, harpsichord, guitar and violin also have a soundboard, which in bowed and plucked instruments is the top as part of the body. Its wood, thickness and slight arching influence tone color and carrying power.
The soundboard should be distinguished from the bridge, which transmits the string vibration to the board, and from the resonating body as a whole, which in bowed instruments also includes back, ribs and air space.
Performance practice
Treat instruments with a delicate soundboard carefully: humidity and temperature affect the wood. When tuning and playing you hear how the board shapes the sound; a well-maintained instrument sounds even and open.