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    Written byLida van der Eijk
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    YoutubeMusic Theory Video SeriesA step-by-step guide to music theory fundamentals. These 60-second videos provide a clear, structured path to understanding how music works, optimized for a full-screen learning experience.YoutubeMusic Theory ShortsMaster music theory concepts in 60 seconds or less. Quick, vertical videos designed to give you essential theory knowledge in a fast-paced, mobile-friendly format.
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    3. Learn music theory with Sonid 14: Perfect Octave

    Learn music theory with Sonid 14: Perfect Octave


    Author: Lida van der Eijk
    July 23, 2025

    Today's topic: "What is a perfect octave?" In this video you will learn how to construct and identify a perfect octave interval in 30 seconds. Including some examples and common mistakes.

    An interval is the distance between two notes.

    To identify an interval you must:

    1 (number) - count the amount of naturals

    2 (quality) - count the semitone steps

    In music theory, a octave (perfect, diminished or augmented) is the interval between a natural and the eighth one above it. For example, the interval between tones C and C is an octave, but the interval between B and B flat is as well.

    Additionally, a perfect octave consists of 12 semitones and is abbreviated with P8.

    Common mistakes are often made when the notes of an interval use different naturals, but musically sound the same. An example of this would be a E to a F flat. Or C to B sharp. Which are both different intervals, but sound like a perfect octave.

    This may sound a little confusing at first, and it probably is. But when advancing in music theory it is an essential skill to understand. With it, you will be able to create chords, scales and progressions.

    So, to correctly construct or identify a perfect octave make sure that you count eight naturals. And there are twelve semitones between the notes.

    That's it, you can now use the perfect octave!

    After watching the video, you can read about [what a perfect octave is](https://sonid.app/musictheory/interval/perfect-octave).


    Music theory libraries
    Chord libraryScale libraryInterval guide
    Music theory libraries
    Chord libraryScale libraryInterval guide

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