Relating the Major Scale to the Major Seventh Chord

If you are confused by any of the terminology used in this section it is suggested that you go back to the previous sections and read the material on note reading, rhythmic notation, intervals, scales, triads, and seventh chord construction.

As discussed in the previous section, if we ascend the major scale in thirds, we derive the first, third, fifth and seventh notes of the scale. These notes make up a major seventh chord.

If we continue up the major scale in thirds, we arrive at the upper extensions of a major seventh chord. Upper extensions are notes above the chord tones that can be added to the chord in order to add tonal shading.

The first upper extension is the ninth. If we continue up in thirds we arrive next at the eleventh and then at the thirteenth. When added to a major seventh chord, the 9th and 13th are also known as color tones because they add tonal shading to the chord. They do not change the characteristic sound of the chord, which is primarily determined by the root, third and seventh of the chord. For this reason, it is common for pianists to add a 9th or 13th to a major seventh chord even if the chord symbol in the music does not specify them.