YOU CANNOT PURCHASE MORE PIANO FOR LESS MONEY ANYWHERE!
A piano is made from natural materials – wood, felt, leather, and wool. All of these materials are known to absorb moisture from the air. As the air gets more humid, the materials absorb more moisture. It is then given up as the air becomes more dry.
The amount of moisture content collected by the natural materials affects their dimensions. This is especially true of the piano’s soundboard. The soundboard is a thin sheet of wood, about 3/8 inch thick, and has a bowed or crowned shape. Blocks of wood called bridges are positioned against the soundboard and press firmly against the strings. As the relative humidity of the air increases, the soundboard’s moisture content increases along with it — which in result swells the wood. The soundboard’s crown then increases with the swelling and intensifies the pressure against the strings. This raises the pitch of the piano. The opposite happens when the relative humidity decreases. High humidity also causes the wooden parts of the piano’s action to swell. This can lead to sticking keys and a sluggish, unresponsive action. As the felts on the hammers swell from the humidity, the sound of the piano can become soft and muffled.
The repeated changes in the dimensions of the wood as the relative humidity rises and falls can eventually damage the piano. The sound board can crack and glue joints can separate. As the pin block repeatedly swells and contracts, the tuning pins that hold the strings can eventually loosen and the piano will no longer hold tune.
Limiting the swings in humidity in the room’s air will limit the changes to the piano. A heated house in the winter usually has a lower than average relative humidity, but in Florida this is usually not a problem. Our problem is the opposite: the humidity is too high in the summer.
Air conditioning reduces the humidity during the summer months, but this is often not quite enough. A stand-alone dehumidifier can reduce the humidity even more, but even this is usually insufficient. The most favorable environment for your piano is a relative humidity ranging between 45% and 70% and a constant temperature of approximately 68˚F (20˚C). Sudden fluctuations in temperature must be avoided.
For more precise regulation of the humidity in the vicinity of the piano’s sensitive sound board, we need to control the humidity inside the piano itself.