A piano goes out of tune even if its not being used.
Generally a piano will drop in pitch 2 to 3 cents a year. A piano can sound perfectly in tune but in fact the whole scale will be flat. The further a technician needs to bring it back up to pitch, the less stable the tuning will be.
I have customers that get their piano or pianos tuned twice a year. I tune the Alexander piano 12 times a year depending on gigs or concerts.
Once a year for a domestic piano is generally good.
Piano tuning is a crucial part of an instruments care. If a piano is out of tune a student can become used to it, and train their ears to be used to the wrong pitch and sound, which can lead to a shock when playing an instrument that is in tune. It is impossible to play a fixed pitch instrument with an out of tune piano.
Occasionally I come across a piano that is down in pitch requiring two or even three tunings before it is stable.
Another kind of maintenance a piano technician will do is regulation and voicing, lesser known to the owner of a piano but this can turn a very average piano into a much more responsive and better sounding one.
On one key of an upright piano there can be up to 25 adjustments that can be made, and on a grand piano up to 35!
I offer Piano tuning and repairs in Dunedin, Timaru and I travel to Christchurch,
If you would like to know more about piano tuning or make a booking feel free to contact me Click Here.