They can be 2, 3, 4 etc.
overtones
Overtone
Harmonic frequencies.
They are all multiples.
All multiples of 8 are also multiples of 2, but not all multiples of 2 are multiples of 8.
Harmonic Series
No, they are not.
overtones
Because that is how harmonics are defined!
These are known as harmonics, or overtones.
They're called "harmonics".
For a waveform containing harmonics, the harmonic frequencies are multiples of what is known as the 'fundamental' frequency. For example, for a waveform that contains 'third harmonics', the fundamental frequency is one-third the frequency of the harmonics. The fundamental frequency of vocal folds the speech mechanism as sound generator.
Harmonics are multiples of the fundamental frequency of the wave.
That are harmonics: fundamental + overtones. Calculations of harmonics from fundamental frequency. Look down to the related links: "Harmonics Calculator".
Overtones.
The definition of fundamental frequency is the lowest frequency of a periodic waveform. Sometimes fundamental frequency is abbreviated by FF, containing the lowest frequency starting from 0.
Fundamental frequency is called the 1st harmonic.The fundamental = 1st harmonic is not an overtone.