There are three key ingredients for keeping a piano in tune: location, humidity control and frequent tuning.
• Location is important. The ideal situation for a piano is a room with constant temperature and humidity. Avoid proximity to frequently open doors and windows, to heaters and fireplaces, to the steam from kitchens and bathrooms, and direct exposure to the sun.
• Humidity control is now a realistic possibility almost regardless of location. Since it is not always practical to keep a room or a large space heated or dry, it makes sense and “cents” to localize the treatment. A covered piano equipped with a humidity-control device will hold its tune remarkably well.
• Frequent tuning assures the player of hearing proper sounds. The more often a piano is tuned, the smaller adjustments are needed to be made each time. The smaller the adjustments, the more stable the tuning will be. The more stable the tuning, the longer it will last. Tune at least twice a year, or every significant weather change. Concert pianos are tuned before every concert, sometimes weekly or daily, just as violins and guitars are tuned before each performance.