Tuning Twice a Year
Piano strings are strung under tremendous tension, averaging 90 kilograms each. Hence, even if the piano is not played, the strings will gradually stretch with the passage of time and the piano will fall out of tune.
Pianos need regular tuning at least twice a year to keep them up to pitch and playing the correct notes. In particular, piano strings stretch a great deal during the first year after purchase. In addition, tuning is a way to check the piano's condition, which is important. Tuning diagnoses potential piano "health" problems.
Regulation involves making minute adjustments to the keyboard and action. The touch of the keys is adjusted, and the keys are leveled.
Tuning is the correction of the pitch of each note by gently re-tightening metal pins called tuning pins around which the strings are wound, using a tool called a tuning hammer.
Voicing involves balancing the volume, tone, and overall sound of the piano by adjusting the hardness of the hammer felts by pricking them with needles using a tool called a picker.