Q: What's up with my piano?
A: Tune in to find out!
To sound their best, all acoustic pianos need tuning...but all piano tunings are not the same! Pitches can sound off or uneven, individually, by their octaves, by the register they’re in, by their relation to standard pitch (A=440) or all the above.
Why Pianos Go Out of Tune
Just as a tightrope walker uses the tension of a taut rope to maintain balance, pianos use the proper tension of the strings to sound in tune. Each string must be set properly. Factors that disturb the correct tension: humidity and usage.
Wood is used to hold the tuning pins secure, to transfer energy from wire to sounding board, and in the sounding board itself. Even with a slight amount moisture in the wood of pianos, this is enough that fluctuations in humidity will slightly cause the wood to slightly expand and or contract, drawing the overall pitch sharp or flat.
As a piano gets played, the force of the hammers also causes tension of the strings to change. That is why playing fortissimo will cause a piano to go out more quickly than playing pianissimo.
When Pianos Should Be Tuned
Everyone’s ears are different and have a different tolerance for what’s ‘in tune’ or not. Most ears can only start to hear pitch differences at 3 cents. Because of this relativity, some ears can detect out of tune notes better than others.
As general advice, I recommend tuning pianos every 6 months for those that are played every day, and 12 months for those that are played a few hours a week. It’s possible a piano will not need a tuning this often, depending on humidity and playing frequency.
The wood in pianos, located in the keys, action parts, bridges, soundboard, and pinblock, contains about 3-4% moisture.
One of the main factors in de-tuning is humidity. Attention should always be paid to the air vents in the room to reduce the amount of direct air flowing onto your piano. Always avoid direct sunlight. Even indirect sunlight in a room for an hour will alter the humidity. Open doors and windows will introduce humidity shifts that can alter a tuning.
A hygrometer is highly recommended to keep a record of the humidity near the piano. If more stabilization is desired, a dehumidifier and/or humidifier for the room is recommended. For the most thorough humidity control, a system called Dampp-Chaser can be installed in your piano.
Ask your technician about the pros and cons for each option.