Many people are not aware that humidity can have a profound effect on the tuning and performance of your piano. Humidity is a measure of how much water vapor is in the air, relative to the maximum amount of water vapor it can hold (that’s why it’s called relative humidity!). Your piano is subject to wide swings in humidity. This is particularly true in the Hudson Valley, where the majority of our clients live. In the summer, humidity levels can go as high as 100%, while in the winter, your heating system can drop the relative humidity in your home into the single digits.
What does this mean for your piano? When the humidity is high, the soundboard and bridges absorb moisture and swell, increasing the tension of the strings and forcing the piano sharp. When the humidity is low, the opposite happens - the soundboard and bridges release moisture and shrink, reducing the downward pressure of the strings and forcing the piano flat. This is why almost all piano manufacturers - and your piano technician - recommend that your piano is tuned twice a year. In addition to forcing your piano out of tune, increased humidity affects the action parts, swelling the wood and increasing friction, which can make your action respond sluggishly (a major cause of “sticking” keys).
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