Soundboards – the important things you should know:

Soundboards are generally made of solid spruce planks that are joined together, though cheaper pianos , such as the Yamaha B3 upright, often use laminates which are similar to plywood.

The tone of pianos depends firstly on the quality of the soundboard.

A top maker chooses close grained spruce and will spend a long time shaping it, making it thinner at the edges and giving it a “crown” or hill, the highest point being the mid treble where the sound needs to be strongest and to be distributed the fastest.

The planks are glued together and ribbed in the opposite direction to the grain as illustrated here. There are thirteen ribs on this soundboard. The ribs carry the sound to the extremities of soundboard. In good pianos these normally have a convex bow shape to encourage the soundboard to maintain its crown.

Grand piano soundboard from below

Soundboard 1b

Important!

Over the years the spruce planks often dry out, leaving a gap between each one. However as it’s the ribs that carry the sound of the piano in the opposite direction to the planks then this gap or split hardly effects the transfer of sound. Nevertheless the gaps are an indication that the piano has dried out at some stage, and this may mean that other more significant work is needed on the piano, such as changing the tuning pins for larger ones.

Soundboard manufacture is highly skilled and firms like Bluthner, Steinway, Bosendorfer and Yamaha (the latter on top range models only) spent a great deal of time sculpturing them, learning from experience what shape produced the best tone.

Grand piano soundboard from above

Grand Piano Soundboard 2b

Soundboard and frame on an upright piano – important information

The soundboard on a top quality piano is made of spruce and the sound is transferred to it from the strings via the bridge. Cheap pianos can have a laminated soundboard similar to plywood and this doesn’t vibrate so freel

The frame in cheaper old upright pianos is often half plate in nearly all pianos made after 1880 is mairony cast iron. The strings are attached to it and a held at great tension.

Upright Piano