Now that Autumn is in full gear for the northern hemisphere, it brings bumper harvest as well as enjoyable cool weather.

However, like what we mentioned before. Among the several things that make pianos go out of tune, seasonal change in humidity is probably the most significant reason.

Being made of wood, which expands and contracts in response to the relative humidity of the environment, piano soundboards swell during the summer months causing more pressure to be exerted on the strings which cause the pitch to go up.

In the autumn and winter when the heat goes on the moisture content in the atmosphere drops and the soundboard shrinks and the pressure on the strings drops causing the piano to go flat.

Meanwhile, as we all know that each string of a piano is wound around a steel tuning pin which is driven into a hole in a plank of wood, the pin block. Over the years seasonal fluctuations in humidity may cause the pin block to loosen its grip on the tuning pins. Cracks may occur in the pin block or tuning pin holes may get enlarged.

Humidity control is the best way to prevent a piano from going out of tune. Basically, please don't put your piano near fireplaces, gas heaters, heating vents, direct sunshine, radiators, or ventilated windows. Sources of heat near a piano may cause the piano to dry excessively. Sunshine can cause heating and drying of the piano, it may also wreck the finish and cause discoloration and color alteration of plastic piano key tops.