Piano Tuning & Regulation
If I'm not using my piano, it shouldn't go out of tune — right?
This may be the most misunderstood thing about pianos. Climate — not playing — is the main reason they drift.
Why pianos go out of tune
This may be the most misunderstood aspect of pianos. A piano can stay at standard pitch (A-440) and still sound out of tune because individual strings drift slightly sharp or flat, causing a “twangy” sound on a note or two — or many. If it's been more than a month or two since the last tuning, that's a sign it's time again.
A piano can also drop in pitch overall, which then takes more tunings to re-stabilize. This usually happens over more than a year and is harder for the average owner to notice.
The three reasons a piano goes out of tune
- Humidity changes, which make the wooden soundboard expand and contract — changing string tension and forcing the piano out of tune.
- String tension. Each of a piano's ~220 strings is pulled to roughly 180 pounds, totaling nearly 20 tons. The strings stretch and the plate and structure move with temperature and humidity, keeping things in near-constant motion.
- Heavy usage. Playing more than a few hours a day (like a practice-room piano) accelerates the process.