The influence of string tension on pitch accuracy.

To understand why a piano goes out of tune, one must first recognize that the piano's structure is under constant pressure. Over 200 strings are each stretched with an average tension of 150 to 200 pounds. Consequently, the cast iron frame and the heavy wooden structure must bear a total tension of 18 to 20 tons. This pressure is not constant. The passage of time, changes in temperature, the release of internal forces, and wear and tear all affect the pressure, leading to the piano's tuning going out of whack.

2. The impact of temperature changes on pitch accuracy.

The soundboard of a piano, akin to the skin of a large drum, is a flexible surface with over 200 strings tightly stretched across it. The large wooden soundboard is highly sensitive to changes in temperature and humidity. In most southern regions of our country, where it is often rainy and humid, the wood expands in this environment, and no paint can protect the soundboard from being affected. On the other hand, most northern regions of our country experience little rain and are dry. During the severe winter, heating is used to combat the cold, resulting in very dry indoor air. The moisture in the soundboard evaporates quickly, causing it to shrink. The continuous expansion and contraction of the soundboard leads to the strings changing accordingly. Moreover, the changes in temperature, which cause expansion and contraction, affect the metal frame and the tension of the strings, leading to tuning issues in the piano.

3. The Influence of Piano Playing on Pitch Accuracy.

During the piano performance, the hammers repeatedly strike the strings. The impact of external force on the strings, combined with the inherent internal stress of the material, naturally increases the tendency for pitch variation. If the performer is a pianist or a piano major at a music academy, their playing force will be significantly greater than that of a beginner, thus having a much greater impact on pitch accuracy.

4. The impact of the tuning pin plate on pitch accuracy.

The string block significantly affects pitch accuracy, as improper fitting of the tuning pins with their holes or loosening due to weather changes can tensionally impact the correctness of the pitch. In most northern regions of our country, drought and sparse rainfall cause wood shrinkage, leading to larger spaces in the string block's pins, widespread loosening of the tuning pins, and the piano running out of tune.

5. The impact of string quality on pitch accuracy.

The quality and pitch of strings are related, and in foreign countries, piano strings are already produced using a special material. However, even these strings undergo changes under the force of tension, a phenomenon known as "tensile relaxation," which is unavoidable due to the plasticity of the strings. Although new pianos are already tuned six to seven times during production, the strings still undergo changes due to tension, making regular tuning even more crucial for new pianos.

6. The impact of piano quality on pitch accuracy.

The inherent quality of a piano, generally speaking, is such that if a brand's piano is of higher quality, due to advanced craftsmanship, skilled technology, especially strict material selection that meets international standards, its stability in pitch will be relatively better.

7. The Impact of Handling and Moving on Piano Tuning.

Pianos that are transported remotely or frequently moved can also experience pitch changes.