The construction of a piano soundboard requires meticulous precision. Key elements such as its convexity, wood thickness, the placement of strings beneath it, and the support structure are all carefully calculated. Variations in design are significant, with builders employing distinct methodologies. Some soundboards are crafted with variable convexity to distribute tension more evenly, while others maintain consistent thickness across the board. Alternatively, some designs feature thicker central areas that taper toward the edges. The positioning and design of the supporting ribs, or "chains," beneath the soundboard also vary widely, as does the contour and edge shaping of the board itself.

Soundboard function
When the pianist strikes a key, the hammer is accelerated towards the string and strikes it. When the string is struck, it absorbs most of the hammer's kinetic energy. The string is set in vibration. There is a deformation in the string which propagates towards the bridge and towards the nut, where it will be reflected and return towards the point of percussion. The transverse deviation is indeed very weak. Each time the wave is reflected against the bridge, it loses some of its energy on the soundboard. The soundboard now functions as a reflective membrane that transfers over and under pressures to the air, which we perceive as the sound of the instrument. The reason why a soundboard is needed is that the string has a very small contact surface with the air. To obtain a full and "carried" sound from the instrument, the vibration of the string must be transferred to a larger surface, capable of receiving the vibrations, which moves in unison and carries forward the vibrations. The hammer supplies the string with energy. The harder the hammer strikes the string, the stronger and shorter the initial impulse will be. This means that the harder the hammer, the more partials there will be in the sound.

Material properties 
Spruce is the preferred material for soundboards due to its lightness and strength. Other materials, such as Douglas fir or plywood, are occasionally used but lack spruce's ideal balance of properties. The thickness of the soundboard and its bonding to the inner rim significantly impact its vibrational behavior. Most soundboards are securely anchored along their entire perimeter, though some older designs feature partially suspended boards. Spruce exhibits anisotropic strength, being significantly more resistant along the grain than across it. For example, a rectangular spruce board with the grain aligned along its longer side will be approximately 25 times stiffer in that direction than if the grain runs along the shorter side. The material's low internal friction contributes to its vibrational efficiency, though friction is slightly higher along the grain compared to across it, with the difference being relatively minimal. This uniformity in vibrational characteristics makes spruce particularly suited for soundboard construction, ensuring consistent resonance and tonal quality.