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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 4: Perfect Prime

    Learn music theory with Sonid 4: Perfect Prime


    Author: Lida van der Eijk
    July 23, 2025

    Today's topic: "What is a perfect unison?" Also called a unison, prime or perfect prime. In this video you will learn how to construct and identify a perfect unison 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

    A perfect prime, or perfect unison, is essentially an interval of two notes of the same pitch. Such as C to C, or D to D.

    However, there are some cases where those two notes are actually using a different natural. And as s such, the interval will be named differently, though the sound may be the same. An example of this would be a C sharp to a D flat. Or E sharp to F.

    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 unison make sure both notes use the same natural. And there are no semitones between the notes (both notes are the same pitch).

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


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

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