What is pitch raising?
By far, the most common procedure a tuner has to do (outside of fine tuning) is a process called pitch raising.
Pianos are always drifting flat, meaning their overall pitch is lowering over time by about 2% per year. 10% will necessitate a pitch raise so if you haven't had the piano tuned in a few years you can bet it will need a pitch raise (in some extreme cases more than one) in addition to the regular tuning. Pitch raising is a special tuning where the overall pitch is brought up higher than A440 and then allowed to settle into place. The piano is then fine tuned immediately afterwards. So basically, it is two tunings in a row.
A pitch raise then generally leaves the tuning unstable and you may need to have the piano tuned again soon, somewhere between a week to three months later. Keep in mind if you have your piano tuned at least once a year you will not have to deal with it going flat and therefore needing the extra work.
Note: brand-new pianos, because of the elasticity of their new strings, drift flat much faster than older, more stable pianos. This is why the manufacturers generally recommend four tunings in the first year of a piano’s life in its new home. From there you can begin the normal schedule of tuning once or twice a year.
Leaving it flat
Sometimes the technician will offer the option to tune the piano normally but leave it flat. We call this “tuning the piano to itself.” This option forgoes the pitch raise and leaves the tuning more stable, but it will be a lower pitch overall. It will still sound clean and in tune.
Some negatives to leaving it flat are:
• It will be challenging to play along with other instruments.
• It will sound somewhat ‘dim’ and have a less pleasing sound because the strings are not at their intended tension.
• Considering the developing ears of students, they will not become accustomed to hearing the notes the way they are supposed to sound as they practice.
Raising the pitch, while common, is not an ideal thing to have to do. It can cause little imperfections in the strings and puts the piano through some degree of stress. Strings may break in the process. In some cases the technician may recommend against raising the pitch if it doesn’t look like the piano can handle it. If you have your piano tuned at least once a year you will never have to deal with raising the pitch and you will ensure the value and tone of your piano for many years to come!