How is a piano tuned?
A piano tuner and piano technician takes great care when tuning a piano or grand piano. The following operations are usually completed during a tuning and undercutting session.
Checking and maintaining tuning pins
The strings of a piano are attached to tuning pins. These tuning pegs have very fine threads and are screwed into the wooden tuning block. You can use a tuning hammer to twist the tuning pegs. By turning the tuning peg to the left, the tension is reduced and the tone of the string goes down as a result. Turning the tuning pin to the right increases the tension and the tone goes up.
Tuning or replacing piano strings
When the piano or grand piano is opened it can be seen that from left to right there are first a number of thick copper-wound strings. These are the bass strings. The lowest octave has only a few thick bass strings. Then the bass strings gradually become thinner and for 1 note there are then 2 strings. If 1 of those two strings is detuned higher or lower than the other, there is an audible swell due to the difference in the frequency of the 2 strings. The same can happen with the non-wound strings, called steel strings. The steel strings almost always form a so-called tri-chord. If not all three strings produce exactly the same frequency when struck, the chord is detuned and a tremor is audible. Strings can also rise or fall in pitch together. Then the chord does not detune but you will hear a tremor when, for example, an octave is struck. Because pianos usually detune slowly, the pianist can get used to the gradual detuning, but at a certain moment the detuning will become more and more audible.
Adjusting the frequency
Usually a piano is tuned at 440 hertz. In the Netherlands and quite a few other countries this is the so-called concert tuning. In France, for example, the official concert tuning is 442 hertz and so it varies a bit depending on each country. Nowadays many orchestras play at 443 hertz.
Pianos are built to be tuned at or around 440 hertz. A few factors play a role in the level of tuning. It is said that strings sound best at breaking tension. Of course it is not 440 hz because strings would break every so often. However, the closer you get to break tension, the nicer the string sounds. By building up a certain tension, the tension on the soundboard or wooden soundboard is increased and that in turn brings a more beautiful sound. Hence, the aim of a piano tuner is to tune the piano around 440 hz.
How does a piano tuner work? Take a look!
I am always happy to explain how the piano or grand piano is tuned by me. My clients are always allowed to watch if they wish. Often it can also be interesting for children to see what a piano looks like inside and how I bring the piano back into tune nicely.