Solid wooden frame which supports the whole construction of the piano. It especially offers resistance to the bending forces which result out of the string tension (approx. 180,000 newton!).
The dampers, in simple terms, are wooden levers with a felt head which rest on the strings when not played. When a note is played, the damper lifts off the string just before the hammer strikes the string. As long as the key is depressed, the damper will not touch the string. After letting go of the key, the damper returns to the string and cuts off the sound. The right pedal raises all the dampers simultaneously.
Anchored in the iron frame, this is a device which holds the end of the string.
The iron frame supports, together with the wooden back-frame bracing, the tension of the 220 strings. This tension is between 15 and 20 tons. The hitch pins for fastening the strings are anchored in the iron frame, which is bolted to the wrest plank and the soundboard brace.
Ivory keys, ebony
Keys used to be made of ivory: a frequently held opinion. It is not true!
Let-off (escapement)
A feature of the action which enables the hammer to fall back several millimetres after striking the string, although the key is still depressed, thus enabling the string to vibrate freely.
Every upright and grand has two pedals. Some have three.
The soundboard is a wooden panel which transmits the string vibrations to the air, thus making the sound audible. The strings are stretched across a bridge which transfers the vibrations to the board. Soundboards are mostly made of timber from slowly growing, mountain spruce trees from high altitudes.
Voicing (or toning)
The hammer felt is pricked with needles to regulate the degree of hardness, thus influencing the tone colour and volume.
A cylindrical, metal part with a square head. The greater part is inserted in the wrest plank. The string is wound around the visible end of the pin. Turning the pin lowers or raises the string tension and the piano can be tuned.
A solid wooden plank in which the tuning pins are driven. The strings are attached to the pins. In an upright the wrest plank is attached to the back frame, and in a grand to the outer rim.