Tuning Basics

The average piano should be tuned twice a year. In New England it is usually humid in the summer, and dry in the winter, and you want to counter these two major changes of the moisture content of the wood. The best advice is to tune your piano when it does not sound good, regardless of whether it has been six months or not. Try to avoid waiting more than a year between tunings.

A piano has more than 230 strings producing a combined total of between 18 and 20 tons of tension. The main support for this tension is the cast iron plate. Also supporting this tension are the wood frame, pin-block, soundboard, and bridges. Anything which affects the position or size of these wood parts causes a change in tension, making the piano go out of tune.

This is the main reason a piano goes out of tune. Every time the temperature changes, or when the humidity level increases or decreases, the wood parts of the piano expand or contract respectively. With this expansion or contraction of the wood parts of a piano, the tension level changes, affecting the tuning.

Piano wire is elastic and begins to stretch as soon as it is tuned. As it stretches the pitch level changes. This is why a new piano might need to be tuned several times before it will maintain its pitch. A new string on an older piano will also need to be tuned frequently until the tension level is stable.

Most pianos can be tuned properly if the structure of the piano is still in good condition. If the tuning pins are loose, the piano will not hold its tune for a reasonable length of time. Loose tuning pins can be caused by a cracked, or dried out pinblock. This problem can prevent proper tuning, and is difficult to fix.

Pitch raising is required when a piano is flat from pitch (A=440), usually at least a quarter step or more. Pitch lowering is required when a piano is sharp from pitch, usually at least a quarter step or more. These problems occur if a piano hasn’t been tuned for several years, or when a piano is in an environment where the humidity changes dramatically each season. Any time a piano requires a substantial increase or decrease in tension it will tend to drift back to where it was. Pitch raising and lowering requires going through the tuning of each note multiple times in one tuning appointment so that the tension can be stable when finished.