What are octaves?

You have probably heard the term octave. But what does it mean?

To say that a note is one octave higher means to say that the note is the same, but it is in a higher section of the instrument.

Imagine a piano. On it, the keys on the left are lower than the keys on the right. If you are pressing the white keys, starting from C, from left to right, the sequence will follow: C, D, E, F, G, A, B, C… continuing in this cycle until the piano keys are finished.

As the notes get higher, it is easy to see that the next C will be higher than the previous one. Whenever a cycle ends and the note returns to C, an octave is completed.

Note that B is the 7th degree of C (as we saw in the article “What are degrees?“), making C the eighth degree. This is why it is called “octave”.

We use the example of C here, but this is valid for any note, as long as it starts and ends on the same note. If we started from D, we would close an octave when we reached D again. The same logic can be applied to an octave below, where the sound gets lower.

Since Western music has 12 notes (12 semitones), we can conclude that an octave comprises the distance of six whole tones. Check below to see how we return to the original note in 6 tones:

one octave is the same of six tones

Just for the sake of curiosity, pianos usually have about 7 octaves.

Go to: Module 3

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