NCVPS AP Music TheoryPresentation by Dr. Tom Moncrief

Inversions of Triads

Inversion of TriadsWhen first learning to identify and spell

chords we spell them in block form. Block form (or snowman stacked form) is when all of the 3rd are in order, stacked on top of one another. Remember, Tertian Harmony is based on the element of this interval of the 3rd.

When the Root of the chord is in the lowest voice (Bass), the chord is in Root Position. Not every chord has the Root as the lowest note and to account for that we identify the inversion that a chord is in.

Inversion of TriadsLet’s take a basic triad. Below is the Triad in

Root Position and also in 1st Inversion. Notice that in both chords the notes are (A, C#, E). We use these notes to identify the Quality and Scale Degree Function of the chord. So, this chord has a Quality of Major and the Root of both of the chords is “A”.

A Major in Root Position A Major Chord in 1st Inversion

Inversion of TriadsThese two chords do have the same pitches,

however they do not sound the same. The sonority of the chord will sound different because of the part of the chord that is in the lowest sounding voice. Our ear will hear that chord in 1st inversion as not being as complete or sonorous than the Root Position chord.

A Major in Root Position A Major Chord in 1st Inversion

Inversion of TriadsLet’s discuss how we notate that a chord is in

an inversion. We use Arabic Figures to notate inversions. Arabic Numbers are the numbers that we use in money transactions (1, 2, 3) as compared to Roman Numerals (I, II, III). A triad that is in first inversion will use the Arabic Number (6) to identify that the triad is in first inversion.

6

Inversion of TriadsNotice that the Root Position triad does not

have any figures underneath it. Because Tertian Harmony is based on 3rds and the Root is the lowest voice, there is no need for figures to further identify the Root Position triad.

6

Inversion of TriadsThe (6) in the first inversion, is notating that

there is a 6th above the lowest note (Bass), from “C#” to A” and a 3rd above from “C#” to “E”. The Arabic Numbers could show this a (6) and (3), however these figures are short hand and the 3rd is assumed in a first inversion triad.

6 3

Inversion of TriadsLet’s take a look at a 1st inversion chord and

figure out how to identify it. First, we must identify all of the notes that are sounded (G, Bb, Eb). Then we must ask if these notes are in Stacked form (in direct 3rds of one another). No, this chord is not. Second, we must rearrange these notes so that they are in direct 3rds or stacked form. The stacked form would be (Eb, G, Bb).

Inversion of TriadsKnowing that the stacked form is (Eb, G, Bb) we

can identify the chord and its quality. The Root of the chord is Eb and the quality of the triad is Major. This is a Eb Major triad, however the Root is not the lowest sounding voice (in the Bass). Because the 3rd of the triad (“G”) is the lowest sounding voice, this chord is in first inversion. We can identify it as an Eb Major Triad in 1st Inversion.

Inversion of TriadsA Triad has three pitches (Root, 3rd and 5th). If the

Root is in the lowest voice (Bass), the triad is in Root Position. Root Position does not require any figures. If the 3rd is in the lowest voice (Bass), the triad is in 1st Inversion. First Inversion uses the Arabic Number (6) to delineate that it is in 1st inversion. If the 5th is in the lowest voice (Bass), the triad is in 2nd inversion and that is what we need to discuss next.

Root Position First Inversion Second Inversion

Inversion of TriadsSecond Inversion Chords have the 5th of the

stacked chord as the lowest sounding pitch (in the Bass). The triad below has the following pitches (E, A, and C#). These pitches are not in order by thirds (because “E” to “A” is a fourth not a third). In order to identify the triad and its quality we must first put them in order by thirds (A, C#, E). This is an A Major Chord, however “A” is not the lowest sounding voice and we must account for that with an inversion figure……

Inversion of TriadsThe inversion figure for the A Major Triad is (6,

4). We must use both of the Arabic Numbers here because if we only used the (6) we would be using the same figure as a 1st inversion triad. The (6) represents an interval of a 6th above the lowest voice (Bass) and (4) represents an interval of a 4th above the lowest voice (Bass). In this chord the interval of the 6th is between the “E” and the “C#” and the 4th is between the “E” and the “A”.

64

Let’s Practice!What is the Root of

this Triad?What is the Quality

of the Triad?What inversion is

this Triad in?

The AnswerWhat is the Root of

this Triad? The notes are (Ab, C, and F) and they form a stacked (F, Ab, C) so the Root is “F”.

What is the Quality of the Triad? Minor, (F, Ab, C) is a minor triad.

What inversion is this Triad in? 1st Inversion, the 3rd “Ab” is in the lowest sounding voice.

Let’s Practice!What is the Root of

this Triad?What is the Quality

of the Triad?What inversion is

this Triad in?

The AnswerWhat is the Root of

this Triad? The notes are (G#, B, and E) and they form a stacked (E, G#, B) so the Root is “E”.

What is the Quality of the Triad? Major, (E, G#, B) is a Major triad.

What inversion is this Triad in? 1st Inversion, the 3rd, “G#” is the lowest sounding voice.

Let’s Practice!What is the Root of

this Triad?What is the Quality

of the Triad?What inversion is

this Triad in?

The AnswerWhat is the Root of

this Triad? The notes are (A, D, and F) and they form a stacked (D, F, A) so the Root is “D”.

What is the Quality of the Triad? Minor, (D, F, A) is a minor triad.

What inversion is this Triad in? 2nd Inversion, the 5th “A” is in the lowest sounding voice.

Let’s Practice!What is the Root of

this Triad?What is the Quality

of the Triad?What inversion is

this Triad in?

The AnswerWhat is the Root of

this Triad? The notes are (F#, A# and C#) and they are already in stacked form so the Root is “F#”.

What is the Quality of the Triad? Major, (F#, A#, C#) is a Major triad.

What inversion is this Triad in? Root Position as the Root is in the lowest sounding voice.

Inversion of TriadsInversions of Triads can be identified by the part of

the triad that is the lowest sounding voice (Bass). A Root Position triad has the Root as the lowest sounding voice. The 1st Inversion Triad has the 3rd as the lowest sounding voice. The 2nd Inversion Triad has the 5th as the lowest sounding voice.

Root Position First Inversion Second Inversion