Piano sound boards are thin boards commonly made of spruce approximately 3/8″ thick glued together and extend from the bottom of the piano on a vertical, and the tail of the piano on a grand, to the pin-block and then across the full width of the piano. The soundboard has a crown which is very important to the tone and resonance of the piano. The back of the soundboard has ribs made of wood that are glued to the soundboard to strengthen and support the crown.
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