Chord construction and formulas: Theory and sound (2023)

A group of notes (usually 3 or more) played together is called an aChord.

Here we will cover the most common chord types using the notes fromC major scalein our examples.

In this lesson:

Download a free PDF of this lesson


A dyad is a set of 2 tones.. They are not technically considered chords according to the strict definition of music theory (which consists of 3 or more distinct tones), but may imply the chordal character of the interval between notes.

A well-known dyad is apower cord, that's just akeynotealong with another note separated by aperfect fifth interval.

In the C major scale, a C 5 power chord is simply the notesC&GRAMM, where C is the root and G is a perfect fifth away:


You can form a dyad from any two notes. Let's try again and take notes.C&mithe C major scale.


In this example, C and E are separated by aMayor 3rd interval. This involves a major key and is important for the most basic chord type: theTriad.

Back to top ↑

The triad

Triads are the most basic form of a chord. They consist of 3 tones:Root, Third Interval, and Fifth Interval.

For example, we can create oneC major triadthe notesC,mi, jGRAMMthe C major scale.


Recall from our dyad examples on the previous page that the notes C and E are separated by a3ra mayorinterval and notesC&GRAMMare separated by aperfect 5Interval. This combination of intervals gives us agreat triad.

Back to top ↑

Seventh chord

A seventh chord consists of asquare root, interval 3, 5 and 7. These chords have a bit more "color" than triads, and you'll often hear them in blues and jazz.

Using the C major scale again, we would take the notesC, E, G and B. This gives us oneC-Hard SevenChord based on the intervals of major 3rd, perfect 5th and major 7th.


As with triads, there are different types of seventh chords. Here are the most common:

Back to top ↑

Added pitch chords

Tone-added chords are triads with 'added' notes except for the seventh interval.

Back to top ↑

Download a free PDF of this lesson

ninth chords

These chords are "extended" beyond a seventh chord by adding an interval of nine. You can also think of a ninth as an interval of a major second one octave above the root.

The fifth interval is often left out of the chord because it doesn't affect its tonality. This also makes it easier for musicians to play these chords on their instrument.

Back to top ↑

chords 11 and 13

These chords in turn extend seventh chords by adding a 11th interval or 13th interval. You can also think of an 11th as a perfect 4th interval one octave above the root, and a 13th as a major sixth interval one octave above the root.

ConMajor 11 und Dominant 11In chords, the major third is often left out because it creates awkward dissonance. You'll often see the fifth interval omitted because it doesn't affect the key of the chord.

Foreach chord 13, usually omits intervals 5, 9, and 11. This is for convenience as they do not affect the "13" character of the chord and are therefore easier for musicians to play.

Back to top ↑

chord inversions

You don't always have to play chords in their scalar order. By rearranging notes, you can create what they are
calledchord inversions.

Inversion moves the root to different places in the chord than the bass note.

The intervals and notes stay the same, but where you can play a C major chord like C-E-G (in the root), you can also play a C major chord with an E in the bass like E-G. -do (first inversion). The chord is the same but sounds a little different.

The root chord is a fairly standard and stable sound, while the 1st and 2nd (and sometimes the inversion of the 3rd with 7th chords) give it a different feel or a wobbly feel.

Inversions are often used to smooth out a chord progression so there aren't awkward jumps between notes in consecutive chords.

Example: Transition from C major (C E G) to A minor (A C E)

Let's start with the chords arranged in their root position, with the root placed at the bottom:

When both chords are in the root, each note between the chords is separated by a wide major sixth interval. It will still sound good since both chords are still in key, but it can sound a bit shrill.

If we invert the A minor chord so that the C note is in the root, we only have 1 note alternating between the chords. Only the G moves to an A in a full step. This will sound really smooth and subtle!

triad inversions

Triads have 2 inversions in addition to their basic position. We use a major triad (1 – 3 – 5) as an example in the table below, but this works for any triad: minor, diminished, augmented, or suspended.

insidefirst investment, the third interval becomes the bass note instead of the root. insidesecond investment, the fifth interval of the chord becomes the bass note instead of the root.

This is reflected in the chord name, e.g. B. Cmaj/E, meaning "a C major chord with E as the bass note."

A quick way to create investments isRaise or lower one of the notes of the triad by an octave. This changes the bass note and creates an inversion.

seventh chord inversions

Since seventh chords have 4 notes, they have an additional inversion. Let's take a major seventh chord as an example, but this will work with any seventh chord.

Again, with each inversion, the bass note is no longer the root of the chord.

Back to top ↑

Do you have a hard time finding the next note or chord when playing or practicing with friends? Jam Pages was made just for you!

Learn more

chord voice

If you change the order of the notes in a chord but the bass note stays the same, you createchord voices.

open voicesSpread the notes over more than an octave. For example, this C major chord is expressed with the root note E, which is an eighth higher than those of C and G.

Chord construction and formulas: Theory and sound (10)

close voicesOrganize the notes tightly. Notice that we moved the E note to the same octave as C and G.

Chord construction and formulas: Theory and sound (11)

As long as the bass note stays the same(changing the bass note creates chord inversions), you can arrange the other notes in the chord however you like to create different voices. They can be used in different ways:

  • Sound Qualities:Closed voices can sound "thick" while open voices can sound "airy".
  • Composition:For smoother transitions between chords.
  • Kompfort:Certain instruments have more comfortable voices for finger placement and stretching.

Back to top ↑

Download a free PDF of this lesson

Structure of chords from keys

next lesson

We use cookies on our website. By clicking on "Accept", you agree to the use of cookies.

Top Articles
Latest Posts
Article information

Author: Twana Towne Ret

Last Updated: 03/16/2023

Views: 5750

Rating: 4.3 / 5 (44 voted)

Reviews: 91% of readers found this page helpful

Author information

Name: Twana Towne Ret

Birthday: 1994-03-19

Address: Apt. 990 97439 Corwin Motorway, Port Eliseoburgh, NM 99144-2618

Phone: +5958753152963

Job: National Specialist

Hobby: Kayaking, Photography, Skydiving, Embroidery, Leather crafting, Orienteering, Cooking

Introduction: My name is Twana Towne Ret, I am a famous, talented, joyous, perfect, powerful, inquisitive, lovely person who loves writing and wants to share my knowledge and understanding with you.