Mon Prof Augmenté
String Harmonics
Age 17 · Music
A stretched string can vibrate in whole-number patterns called harmonics. Their frequencies stand in the ratios 1:2:3:4, which produce the octave, fifth, and fourth.
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In the picture
- The single arc: the fundamental vibration, with frequency ratio 1.
- The center still point: the node between two arcs, showing the second harmonic at frequency ratio 2.
- A still point in the three-arc pattern: a node of the third harmonic, whose ratio to the second harmonic is 3:2, a fifth.
- A still point in the four-arc pattern: a node of the fourth harmonic, whose ratio to the third harmonic is 4:3, a fourth.
Examples
- A guitarist lightly touches a string at the twelfth fret to hear a bell-like harmonic.
- A violinist touches a string at a node while bowing to produce a clear harmonic.
Key takeaways
- Harmonics are whole-number multiples of the fundamental frequency.
- The frequency ratios 2:1, 3:2, and 4:3 correspond to the octave, fifth, and fourth.
Quiz: String Harmonics (Age 17)
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What are the frequencies of harmonics in relation to the fundamental frequency?
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Which frequency ratio corresponds to the octave?
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When the third harmonic is compared with the second harmonic, which interval does their frequency ratio produce?
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