Piano tuning is an ongoing battle with the conditions in which a piano is kept. The pianist who has a keen ear and the concert pianist who demands perfection, both expect the piano tuner to have the piano in tune whatever the weather. Achieving this golden goal can be done only by a period of over-tuning the piano. Only when a degree of tuning stability is established, can the time between tunings can be lengthened.
One thing is certain: if while tuning a piano, the pitch has been raised, say, half a semitone, it will take a while for the piano to settle nicely in tune at that higher pitch. So it is quite possible to have a piano tuned, only to find that all too quickly, it loses that recently-tuned sound. This is not the fault of the tuner!
From the tuner's point of view, a change in pitch is always countered by the stretch of the strings. Altering the pitch of a piano is like pushing something heavy up a slope. Even when the tuner thinks the pitch of the strings are going to stay where he put it, a force - like the downward pull of gravity, fights back as if it would prefer the tuning to go back where it was!
It is a mistake to think that because the piano was tuned last week, last month, last year or 2 years ago, it will not need tuning again. As a general rule, a piano should be tuned about twice a year and definitely not left longer than a year. If you have a keen ear, you may find the piano needs to be tuned 3 times a year!
© Steve Burden