Harmonic Analysis Tool

• See below for explanations, examples and other details

The harmonic analyzer tool understands these chords:

How to use the harmonic analyzer tool

Overview

The tool helps you analyze and understand chord progressions. It allows you to enter a sequence of chords and read the following information:

• Chord notes – The notes that make up the chords.
• Intervals – The chords' internal interval structure.
• Voicings – A graphic that shows how the notes move from one chord to the next.
• Parent Scales – All the scales that are related to the chords.
• Tonal Centers – The tonal centers (and related key changes) implicit in the progression.

Here are all the details:

Entering the chords

You can write a chord progression in the above text area and click the [Analyze] button to see the results.

Use spaces to separate the different chords. Don't use spaces inside chords. You can enter up to 20 chords at a time.

The supported types of chords are listed above.

The tool also understands a few common variations of the chord types. For example, Cm7, C-7, and Cmin7 are all understood. If in doubt, use the codes in the chord table above.

The tool understands both C-D-E and Do-Re-Mi chord notations. The results are displayed with the same notation used as the input.

The tool skips the chords that it cannot decode.

Chords notes

After analyzing a progression, the first thing that the tool reports is simply the name of the notes that constitute the chords.

So, for example, if you enter a Cmaj (C major) chord the analyzer writes the notes C E G under it, which are the notes that produce the C major chord.

Benefits:

You don't need to read all the chord notes to understand the progression, but sometimes it can be useful to have them written there.

Ideally, though, a competent musician should know the notes that make up the various chords pretty much effortlessly and automatically. Having those notes always written there can help you gradually familiarize with them even without making special efforts.

Chord structures

Right below the chord notes are the intervals that define the chord, i.e. the chord structure.

For example, the C major chord is made of the notes C-E-G, and its structure is R-M3-P5 which is shorthand for "Root", "Major 3rd", and "Perfect 5th".

This means that the C major chord is made of the note C (the Root, or "R"), the note E (a Major 3rd, or "M3", up from C), and the note G (a Perfect 5th, or "P5" up from C).

A table with all the intervals is displayed in Appendix 1 at the bottom of the page.

Benefits

Like with chord notes, it's very desirable for a musician to know the structure of all the chords that one uses. Having this structure always available in front of your eyes is both a useful reference when you need it, and also a way of gradually memorizing it without conscious effort.

Voicings

The voicings row contains 12 lines representing one octave of notes (from C on the bottom to B on the top). Under each chord, the chord's notes are highlighted in red.

This graphic helps you literally see how the various notes -- the various "voices" -- move up and down from one chord to the next.

Benefits

Seeing the chord progression visualized in this way gives you a lot of information in an intuitive and easily understandable way.

For example, one useful piece of information that is clearly visualized in this graphics is the "distance" between one chord and the next. In particular, when two nearby chords have two or three notes in common, they can be considered closely related and most likely belong to the same tonal center.

Furthermore, if while watching the graphic you can also play or listen to the chord progression, you will probably get many other insights.

As another example, if you are experimenting with a chord progression, and you are not completely satisfied with a certain chord or a certain modulation, having a visual display of the chords' notes could give you a tip on which note to change to produce a different and better effect.

Parent scales

A "parent scale" of a chord is simply a scale whose notes can produce the given chord.

For example, the C major scale (C-D-E-F-G-A-B) is a parent scale of the C major chord (C-E-G) because all the chord notes are present in the scale.

The G major scale (G-A-B-C-D-E-F#) is also a parent scale of C major chord because it also contains the C-E-G notes. On the other hand, the A major scale (A-B-C#-D#-E-F#-G#) is not a parent scale of the C major chord because it doesn't contain all the chord tones (it contains the E but it doesn't contain C or G)

Major and minor chords have several possible parent scales. For example, the C major chord can be derived from the C major scale, from the G major scale, from the F major scale, and from the E minor harmonic scale. Other chords, such as the Dominant seventh, have only one major and one minor harmonic parent scale. All these scales are listed in the Parent Scales row.

Benefits

In general, for composition or improvisation purposes, the relationship between scales and chords is fundamental. And in particular, when you have a chord progression and you need to compose or improvise a melody on it, one of the first things you'll need to know is which scale or scales you may use as the primary source of notes.

The more you familiarize with this type of harmonic analysis, the easier it will become for you to instantly know which scales are related to the different chords.

Tonal Centers

When two or more successive chords have a parent scale in common, that common underlying key is called a "tonal center".

A tune may have a single tonal center from beginning to end (like many pop and rock songs for example) or have a few different ones (for example, the verse and chorus parts could be in different keys and therefore produce different tonal centers). In Jazz sometimes the key changes very often and the improviser has to be constantly changing tonal center accordingly.

When analyzing the chords, this tool explores all the possible tonal centers and displays them as different colored blocks. The parent scale of that tonal center is written inside each block.

So, for example, if the analyzer finds that the first three chords can be grouped as a C major tonal center and that the next three chords can be grouped in a D minor harmonic tonal center, it will place a colored block with "C" under the first three chords, and another colored block marked "D mh" under those other three chords. (mh stands for Minor Harmonic scale. If no scale is indicated, it means a standard major scale)

Benefits

Determining the tonal centers of a chord progression is a fundamental step when preparing for improvisation on those chords. If this process is still difficult for you, use the analyzer tool with different chord progressions, observe the relationship between chords, parent scales and tonal centers, and you will soon learn to do it by yourself.

Examples

Here are a few common chord progressions. You can click and see how they get analyzed.

I-VI-II-V progression, C major, triads:

I-VI-II-V progression, C major, seventh chords:

two consecutive II-V-I progressions, in D and in C

Common pop-rock progression in C

Common pop-rock progression in D minor (F major tonal center)

Pachelbel Canon in D

Note on major vs. minor tonal centers

Every major key, or major tonal center, is associated to a corresponding relative minor key and tonal center.

For example, the relative minor key of C major is A minor, and the relative major key of C minor is Eb major. (A relative minor key is always a minor third below the relative major key)

This analyzer tool shows the tonal center always as the major scale, but depending on the melody of the tune (not analyzed here) the tonal center may be equally described in terms of either the major or relative minor key.

In practice this makes little difference -- when you see a C major tonal center, you'll know that you can use the C major scale, or the A minor scale, which is the same thing.

A table with the list of all the corresponding major and minor keys is displayed in Appendix 2 at the bottom of the page.

While I avoided writing both the major and minor relative keys in the tonal center blocks for simplicity, I may add that feature if there is a significant request for it.

Related MTC Courses

These principles of harmonic analysis are uses in several places in the Musician Training Center software.

The Improvisation By Degrees course, for example, trains you extensively in mastering the chord notes and the parent scales as the basis for improvisation.

The Guitar Scales Method includes a play-along tool where you train play the parent scales of all kinds of chords, until the mechanism becomes effortless and automatic.

For more details, and to see these interactive courses in action, download Musician Training Center and try it for yourself.

Support

If you have any questions, or if you'd like to suggest some additions to this harmonic analyzer, please contact support@micrologus.com

Appendix 1 -- Intervals table

Appendix 2 -- Relative Major and Minor Scales table

P.S. Thanks to Thomas Creveaux for dim7 improvements.