Natural Harmonics have been used for centuries for many purposes.
One of the first and most practical ones is to rapidly change position in the instrument, especially on the Cello, when the distances are much larger than other string instruments such as the Viola or the Violin.
What is the difference between a vibrato sound and a natural harmonic?
The sound that we can apply a technique called “vibrato” (from the Italian: “vibrated.”) is usually the most commonly used technique as it provides an expressive and more vibrant sound to the music.
Another reason the vibrato sound is used is that the performer can adjust the tunning rapidly and efficiently, while when we use natural harmonics, the tunning is fixed.
The use of natural harmonics can represent a problem if the performer is already playing higher or lower than he or she is supposed to. But the effect overall is a tranquil and ethereal resulting timbre that in the last century many composers deliberately asked for the performer to use in their music.
Notation of natural harmonics
1.- A small circle over the note intended to sound as a harmonic
2.- A diamond-shaped note at the pitch where the node producing the desired note may be found on the string.
The overtone series and its connection with Natural Harmonics
Each string has multiple sounds related to the main or fundamental, and they are produced by the stimulation of certain areas or “nodes” on the string. Each string has the same mathematical relation. For piano students, this is very simple to see as they have a broad scope of notes, while for string players, this knowledge is somewhat impractical to learn, but necessary nevertheless.
Even some piano teachers don’t possess this knowledge, although it helps to understand more complex concepts such as Harmony and tone production.
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