Why That Chord Note Is Actually a 10th
31sThis reveals a common music theory misconception that makes viewers see intervals in a new light.
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This micro-lesson explains how the interval of a tenth arises in chord voicings when the third is played an octave higher than the root. Using G major, A minor, and a B bass with D on top, it shows how the same chord tones can be reinterpreted while preserving the tenth interval.
Chapters
[00:03]
G major triad construction
G major triad is built G-B-D (1st, 3rd, 5th). The B (third) is not played in the same octave as the G root; it is played a full octave higher.
[00:18]
Third becomes a 10th
When the third of a chord is played up a full octave, it is no longer called a third; it is called a 10th.
[00:31]
A minor with C on top
An A bass note with a C on top is also a distance of a tenth. The C is a flat third in relation to A, creating an A minor triad, but it is separated by an octave.
[00:47]
B bass with D on top
A B in the bass with a D on top implies either B minor (B with D as the minor third up an octave) or a G chord played off the B note.
[01:14]
The interval is a tenth or minor 10th
In all these examples, the interval between the bass and the top note is a tenth (or a minor 10th when the third is flat).
Study Flashcards (6)
What is the interval called when a chord's third is played an octave higher than the root?
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What is the interval called when a chord's third is played an octave higher than the root?
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A 10th (or minor 10th if the third is flat).
00:18
How is a G major triad constructed?
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How is a G major triad constructed?
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G, B, D — root, third, fifth.
00:03
Why is the B note in the G major triad called a 10th instead of a 3rd?
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Why is the B note in the G major triad called a 10th instead of a 3rd?
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Because it is played a full octave higher than the G root note.
00:18
What chord does an A bass with a C on top create?
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What chord does an A bass with a C on top create?
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A minor triad, with C as the flat third related to A.
00:31
What two chord possibilities are implied by a B bass with a D on top?
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What two chord possibilities are implied by a B bass with a D on top?
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B minor (B-D minor third up an octave) or a G chord played off the B note.
00:47
What is the interval between B and D when D is on top an octave higher?
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What is the interval between B and D when D is on top an octave higher?
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A minor 10th.
01:14
💡 Key Takeaways
🔧
Tenths in G major
The third being an octave higher changes the interval name and voicing color.
00:03
⚖️
Third becomes a 10th
Interval naming depends on octave displacement, a core principle in music theory.
00:18
💡
A minor via octave-displaced third
The same principle applies to minor triads, showing a consistent pattern.
00:31
💡
Ambiguous chord implications
The same interval can imply different chords depending on context, a creative tool for composers.
00:47Full Transcript
[00:03] now G major Triad is constructed GB d 1 through 5 so the B note the third and the root note are the only notes really in this chord but importantly the B note the third is not being played in the same octave as the G note it's not being
[00:18] played like this it's being played like [Music] this that third is being played up a full octave and so instead of calling it a third we call it a 10th if we go to
[00:31] a third we call it a 10th if we go to the next chord we have the a base note and the C note on top that is also a distance of a tenth here we have a c e where the C is a flat three in relation to a which
[00:47] creates the A Minor triad but it is again separated by that octave if we go [Music] chord we get a B in the base and a d on top and this could imply either a B minor where we have the b in the base
[01:02] and the D on top as the minor third up an octave or it could also imply a G chord being played off the B note either way we have again that interval of a
[01:14] way we have again that interval of a tenth or a minor 10
