Why do I need my piano tuned ?
First answer is short and obvious. . . it will sound better. A more in depth answer. . . A piano naturally goes out of tune due to changes in temperature, changes in humidity, and regular usage causing the strings to stretch when struck. This is normal and happens to every piano. It is true that some pianos hold pitch better than others, but even they need to be maintained. A piano goes out of tune very gradually and many times is not noticed by the players & owners (see: story of the frog in gradually boiling water).
How often should I have my piano tuned?
Twice a year is standard for keeping your piano in tune. The condition, newness of strings, tuning pegs, how much the piano is played, and how picky you are will determine the frequency of tunings (anywhere from 1 to 3 times a year). Many good pianos that have been worn in and serviced regularly can hold a decent pitch with one tuning a year.
If you don’t keep your piano in tune, the string tension will fall over time, making it difficult to bring back to its original condition (bringing all the strings up to A440 when it hasn’t been tuned for years, will drastically change the tension, and potentially cause problems).
What makes my piano go out of tune?
The most common reason pianos go out of tune is the change in humidity from day to day. When humidity levels change, the moisture content of the wood in the piano swells or shrinks, changing the tension of the strings. Pianos are designed to be in a 42% humidity environment. Installation of a humidity control system can reduce the effects of humidity changes. Other common reasons pianos go out of tune are from being moved or being played hard.