Advanced Theory

This is a page for discussing more advanced keys and scales.

Scales are the foundation on which most music is based. A scale is made up of a series of tones arranged in a specific interval pattern. An interval is the distance between two tones, the smallest of which is called a half-step (H). A half step corresponds to the closest distance between two piano keys. A whole-step (W) is equal to the distance of two half-steps. The quality of a scale–whether it is major, minor, etc.–is determined by the arrangement of half-steps and whole-steps (particularly, the interval to the 3rd scale step).

Most melodies and chord progressions will be constructed using notes from the scale of the song. The key of a song is technically the chord that it resolves to, which is generally based on the root note of the scale and either major or minor.

Here is a description of the different types of scales, with their interval patterns:

This is the most common major scale mode, and has a half step between the 3rd and 4th degrees and another between the 7th and 8th degrees. All other scale steps are separated from their neighbors by a whole step.

W - W - H - W - W - W - H

• Tip: The C major scale uses all white notes.

There are 3 main types of minor scales: natural (Aeolian), harmonic and melodic. All major scales have a corresponding relative minor scale, which is located 3 half-steps below the major scale's tonic note.

This is the most common minor scale, and uses the same notes as the relative major scale.

W - H - W - W - H - W - W

• Tip: The A natural minor scale uses all white notes.

This is the same as a natural minor with a raised 6th, and also the dorian mode. This scale has half-steps between scale steps 2 & 3, 5 & 6, and 7 & 8. Notice the distance between scale steps 6 & 7 is a minor third.

W - H - W - W - H - W+H - H

This scale's ascending order finds half steps between 2 & 3 and between 7 & 8. Unlike any of the other scales, melodic minor scales have a different descending order. The descending order has half-steps between degrees 6 & 5 and between 3 & 2, with a whole-step between steps 8 & 7.

W - H - W - W - W - W - H

W - W - H - W - W - H - W

(same as natural minor)

This scale is the same as the melodic minor scale except its descending pattern is the same as its ascending pattern.

W - H - W - W - W - W - H

These types of scales are generally built off different degrees of the major scale. Some can be viewed as variations of the normal major and minor scales. Here is a summary of the most common variations:

• Phrygian (Minor with a lowered 2nd)
• Dorian (Minor with a raised 6th)
• Lydian (Major with a raised 4th)
• Mixolydian (Major with a lowered 7th)

Note: these are the modes which Rapid Evolution can currently detect.

For any given mode, there is a relative mode of every type. Knowing the modes of your songs can make for more accurate harmonic matches, see Mixing Harmonically for more information.

Here is a summary of the different modes:

This is the same as the natural minor scale (see above).

This is the same as the normal major scale (see above).

This scale begins on the 2nd degree of the major scale. It resembles the natural minor scale with a sharpened 6th.

W - H - W - W - W - H - W

• Tip: The D Dorian scale uses all white notes.

This scale begins on the third degree of the major scale. It resembles the natural minor scale with a flatted 2nd.

H - W - W - W - H - W - W

• Tip: The E Dorian scale uses all white notes.

This scale begins on the 4th degree of the major scale. It resembles the major scale with a sharpened 4th.

W - W - W - H - W - W - H

• Tip: The F Lydian scale uses all white notes.

This scale is just like the Lydian scale except the 7th degree of the scale is flatted.

W - W - W - H - W - H - W

This scale begins on the 5th degree of the major scale. It resembles the major scale with a flatted 7th.

W - W - H - W - W - H - W

• Tip: The G Mixolydian scale uses all white notes.

This scale begins on the 7th degree of the major scale.

H - W - W - H - W - W - W

• Tip: The B Locrian scale uses all white notes.

The pentatonic scales are 5 note scales. These scales can be heard in the solos of many rock and blues guitar players.

W - W - W+H - W - W+H

W+H - W - W - W+H + W

This scale can be found in a variety of blues, rock and jazz styles.

W+H - H - H - H - H - W+H + W

This scale has the simplest formula–it consists of all whole-steps. Unlike traditional scales, the whole tone scales do not contain basic intervals like the perfect 4th, perfect 5th or the leading tone.

Impressionist composers of the early 20th century (such as Claude Debussy) incorporated the use of whole tone scales into their musical style.

W - W - W - W - W - W

This is a technique used in constructing chord progressions. The tonic, or root, is used as the base note, and melodic scales are chosen according to the chords that lie beneath them.

The 7 modern modes are all connected to each other by diatonic shifts; that is, C Ionian (C-D-E-F-G-A-B-C) is also D Dorian (D-E-F-G-A-B-C-D) and F Lydian (F-G-A-B-C-D-E-F). Thus, each of the 7 modes of any of the 12 major keys is also a mode for another 6 of the keys.

Pitch axis theory suggests that for each mode, there is a chord that accompanies it. When that chord occurs, the corresponding mode should be used for the melody or for soloing.

The more common modes, along with their chords: