The essence of a piano’s sound stems from the soundboard.
The soundboard converts the vibrations of the strings and is therefore responsible for the instrument’s tone. It has a large vibrating surface, needs to withstand massive internal strain and is often called the heart of the piano. Spruce is the most popular material of choice for soundboards, but as it is a natural product the quality can vary.
The direction of the grain, straightness and tightness play a major part in determining the tone of a piano. Petrof use only top quality wood in their soundboards and they are made exclusively from narrow ringed, specially selected, radially-cut resonance spruce grown in mountain areas, 1000m above sea level.
Another feature of a soundboard that affects the tone is the shape. A precisely tapered soundboard, as in the Petrof Master and Standard series of grand pianos, vibrates more freely, creating and projecting a bigger sound than a soundboard with a consistent thickness.
Unlike most piano manufacturers, Petrof produces the soundboards themselves, along with the keyboards, hammers, strings and metal parts. High quality European beech is used in the production of the bridges. The high quality spruce and beech wood is also used for building the skeletons, ensuring the rigid and stabile construction in each and every instrument.