Technical Questions

What is meant by ‘overstrung’ or straight-strung?

This refers mainly to upright pianos, as there are relatively few grands without overstrung frames. In an overstrung frame, the diagonal lengths of most of the strings provide a richer sound than its straight-strung counterpart. Take a look at Types of Upright Pianos for more details.

What is an ‘underdamper’ action?

All piano actions are fitted with a damping system; otherwise each note struck would continue to sound until those strings stop vibrating. The underdamper piano system is more efficient as the dampers are positioned below the hammers, and operate via damper-springs. This system is found in the better quality traditional uprights and in all modern ones.

What is ‘concert pitch’?

This is the frequency to which all musical instruments are set or tuned. It is known as A440 pitch standard.

How does an iron frame differ from a wooden frame?

The frame is the structure to which the strings are attached inside. Before the 1880s many uprights were made with heavy wooden bracings at the rear to take the tension. The cast-iron frame was later designed to give the instrument added stability, higher strain and consequently a superior tone. Almost all pianos made after c.1890 were built with iron frames.

What causes keys (notes) to stick or malfunction?

Various causes: Dampness, lack of use for a sustained period; dirt or minor objects; wear & tear; corrosion & rust of metal parts; over-use or abuse; heavy or sustained use without maintenance; housed in room where temperature unsuitable (i.e. very hot/dry or cold & damp or very variable); warped keys, etc.

What does ‘Regulation of Touch’ mean?

This refers to the evenness of pressure between each note and a crisp repetition, accompanied by effective damping. This work is carried out every so often by a trained technician or Tuner.
Please note – Do not attempt to adjust the action yourself; always ask a professional to do this work.


H Burniston

I am delighted to have the piano back at home. It is superb, the tone and touch are superb and the case looks magnificent. I am very pleased to have such a good friend returned to such beautiful condition and am grateful for your efforts of craftsmanship and professionalism.

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Specialists in piano restoration since 1977

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