After the piano has been used for a period of time, the percussion mechanism of the piano has undergone thousands of movements, and some parts that are easy to wear are worn to varying degrees, which leads to the imbalance of stroke proportion and coordination of the percussion mechanism, resulting in poor touch, and the change of temperature and humidity will also lead to some parts of the piano not working well, so the piano should be adjusted regularly. Including the adjustment of the mechanical parts that make up the linkage, keyboard, pedal and escapement mechanism, to compensate for the wear of felt and the change of the size of wood parts. Tuning can ensure the piano's even touch, quick repetition and wide dynamic range. In grand piano, each note can have 35 tuning points, while in upright piano, there are 25, so tuning is a highly technical job, which takes a lot of time.
There will be many signs that the piano needs adjustment. When the performance of fast or Legato passages is limited, it means that the piano needs to be tuned, not your playing speed needs to be strengthened. Loose dampers, keyboards and pedals, uneven keyboard height and heavy touch will all affect the sensitivity of fingers to speed and hammer control. Untuned pianos not only have poor expressive force, but also have a shortened life.