What is this? This is a natural tone overtone series at the reference frequency of 1 hertz, the original tone.

What is an overtone series? These are tones that resonate when a tone is sounded.

1 hertz is usually referred to as the tone C. It is usually audible to humans from 16 hertz. 16 Hertz is an octave of one Hertz.

An octave means the doubling of a frequency.

These are further octaves: 1 2 4 8 16 32 64 128 256 512 1024 2048 4096.

The natural tone overtone series here simply follows the natural numbers.

The natural numbers are the numbers used in counting.

And one usually starts counting at 1. This is what the creator of the natural tone overtone series did. Who was that? God?

Maybe. In any case, however, the lawgiver of the universe has made that. Because: this natural tone overtone series follows a cosmic, eternal, unchangeable law. No human being can change this.

Why also. There is no simpler way. All truth is simple.

And infinite: there are infinitely many overtones of a fundamental tone. They all sound at the same time.

It becomes more complicated if the fundamental does not have 1 hertz, but for example 3 hertz.

Because:
The frequencies of the overtones (partials) are integer multiples of the fundamental frequency. This mathematical relationship is called a “harmonic series”.

This means that the frequency difference between two partials is always identical to the fundamental frequency.

fundamental frequency = 3 hertz
1st overtone = 3+3=6 Hertz
2nd overtone = 6+3=9 Hertz
etc.

The natural tone overtone series is a natural tuning and a pure tuning.
The equal temperament commonly used in the West, on the other hand, is unnatural and due to the requirements of certain instruments.

Of course, the natural tuning sounds more natural.