The Chromatic Scale
The chromatic scale contains every possible note used in western music. All of its notes are one semitone apart (on the guitar a semitone is one fret). The degrees of the major scale can be identified by using the numbers 1 to 7 as shown in the C major scale (C Ionian) which contains all of the natural notes (natural meaning no sharps or flats).
By adding all of the possible extra notes in between the natural notes of the C major scale, the C chromatic scale is created.
The "in between" notes can be described as either sharps or flats. Because of the way modes and chords are constructed, flats are used more often than sharps. Here once again is the C chromatic scale with scale degrees written under the notes. The scale degrees written here relate to the natural notes and the flat notes. The sharps are enharmonic equivalents, which means they are the same pitch (e.g., C# = Db and F# = Gb).
As mentioned earlier, is possible to create many different types of chords by adding notes on top of triads. For example, by adding the 7th degree of the scale to a C major triad, the C major seventh chord is created (Cmaj7). However, by adding the flattened 7th degree to the same C major triad, the C seventh chord is created (C7).
By flattening the 3rd degree of the C major triad, it becomes a C minor triad (Cm). By adding a flattened 7th degree to the C minor triad, a C minor seventh chord (Cm7) is created. Many chords can be created by slight variations to these basic chords. The combination of degrees used in any chord is called the chord formula. The formulas for the most common types of chords are shown here along with an example of each chord as they relate to the key of C.
Major Chord Formula
Minor Chord Formula
Diminished Chord Formula
Augmented Chord Formula
Major Seventh Chord Formula
Seventh Chord Formula
Minor Seventh Chord Formula
Minor Seven Flat Five Chord Formula
These are just the most common chords used in music, there are many other extensions and variations as well. (for more information on chords and chord formulas, see Progressive Jazz Guitar ).
By applying the formulas for seventh chords to the C major scale, the following series of chords is created. These are called scale tone seventh chords.
When numbering chords within a key, Roman numerals are used. This makes it clear that a chord is being described rather than a single note (scale degree) which would be indicated by a number (1, 2, b 3, #4 etc.).
This example shows the seven modes derived from the C major scale played against the seven scale tone seventh chords from the key of C major.
Because each seventh chord contains four notes of the mode it relates to, modes work extremely well over seventh chords. Listen to the sound of this line using the D Dorian mode over a Dm7 chord. Try playing some of the other examples you have learned against seventh chords as well as experimenting and creating some of your own melodies.
