Tuning unisons is arguably one of the most important skills in piano tuning.

An out-of-tune unison is the most common reason you will be called back to a customer's home.

So, what is an in-tune unison, and how do we produce one?

Well, producing one involves a few more descriptions and practice, but describing scientifically what one is, is relatively simple.

It is highly recommended that you check out my videos on the following subjects if you are not familiar with the topics:

The Harmonic Series

What Are Beats?

The Physics of Unisons

Whenever we play a string, there are multiple simultaneous frequencies produced. These are called partials.

Two strings that are matched, should have the same partials.

When these two strings are the same frequency,
then each of the partial pairs will have the same frequency
and there will be no beating at any partial.

If the strings are not at the same frequency,
there will be beating at the higher partials.
The higher the partial, the faster the beating,
for matched strings.

Lesson 6 – What is an In Tune Unison?

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