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The octave doubles the vibration
Age 15 · Music
An octave is a 2:1 frequency ratio, so the higher note vibrates twice as fast as the lower one. Our ears hear these two notes as the same note at different heights.
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Age 15: open this week
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In the picture
- Lower note wave: a few vibrations in a given time
- Higher note wave: twice as many vibrations in the same time
- Lower key: the starting note of the octave
- Higher key: the same note name, one octave up, vibrating twice as fast
Examples
- Tuning A at 220 Hz and then at 440 Hz gives the same note, an octave higher.
- A man and a woman singing the same song together often sing an octave apart.
Key takeaways
- An octave is a 2:1 frequency ratio.
- Double the frequency means the same note, one octave higher.
Quiz: The octave doubles the vibration (Age 15)
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What is the frequency ratio between two notes that are one octave apart?
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A note vibrates 200 times per second. How many times per second does the same note one octave higher vibrate?
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How do our ears hear two notes that are exactly one octave apart?
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