Piano Tuning

Why does a piano go out of tune?

Piano strings are under a great deal of tension which is supported by the frame, plate, pin block, piano tuning pins, bridges and sound board. Anything which affects the positions of these parts will cause a change in tension and make the piano go out of tune.

Owner_Piano

 

Humidity

Even though a soundboard is varnished, moisture from the air can seep into and out of the wood, causing the crown to increase and diminish. This is the most important factor causing a good piano to go out of tune. A typical piano goes sharp in the spring when rain increases the humidity and thus the crown, and flat again in the early winter when the dry heat of the furnace removes moisture from the soundboard, diminishing the crown. This seasonable pitch change is noticeably absent from pianos which are kept in climate controlled (temperature and humidity controlled) environments.
Humidity

 

Temperature Changes

When the temperature rises, the soundboard expands and increases its push on the strings. Since the room temperature surrounding a typical piano usually stays within 20┬░ or so, this factor does not affect the piano tuning as much as humidity does. Temperature changes also have a slight effect on the strings, frame and plate, but this factor is even less important.
Temp

 

Stretching of the Strings

New music wire is very elastic; it begins to stretch as soon as it is pulled up to pitch. New strings stretch the most during their first few years in a piano. Because of its stretching, many new pianos sink a quarter step flat within a few months after each tuning, for two or three years; then the stretching decreases, and the pitch becomes stable for longer periods of time. Some  professional piano tuning,makers and rebuilders stretch their new strings with a small roller immediately after a piano is pulled up to pitch. This procedure can be effective, but if overdone it may cause objectionable false beats in the treble.
Stretching

 

Loose Tuning Pins

This factor does not enter into the tuning of a good quality new piano. The pins in a new piano should be so tight that the string tension does not cause them to turn. In an older piano, however, which has been exposed to regular seasonal humidity changes for many years, the pin block loses its tight grip on the pins, from continual expansion and contraction. When the pins get loose enough, the strings rotate them slowly in the pin block and the pitch gradually goes down. Piano’s which are transferred from a wet to a dry climate tend to get loose tuning pins.
Slipping

 

Playing

The louder and more often a piano is played, the faster it goes out of tune. A piano with tight tuning pins is not “knocked” out of tune as fast, of course, as one with loose pins. But playing is a factor even in fine quality pianos.
Playing

 

Summary

Any piano has one or more factors at work to make it go out of tune. In addition, a poor tuner can leave a piano in tune but in a state that it will not stay that way very long. Some of these factors may be controlled by skill of the tuner; other may be corrected only by restringing or by controlling the climate. Humidity and temperature changes and hard use normally affect even a fine piano: that is why pianos must be tuned regularly. How often should a piano be tuned? This depends upon the condition of the piano and the musical demands of the owner. A piano which is mainly used as a piece of furniture probably would not “need” tuning more than once a year. A piano which is in regular use and is in good condition may get by with being tuned twice a year, each time a seasonal humidity change. A piano given a daily workout by a professional musician or serious student might need monthly or even more frequent ┬ápiano tuning.
Summary
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