by Stefon Pizzuto

In previous lessons we have discussed the construction of chords and chord progressions and learned how they relate to the bass guitar. We also talked about substitute chords and potential bass lines we could play over them. Today we are going one step further by studying the diatonic 7ths of the major and minor keys. This will allow us to determine the quality of any chord that naturally appears in any given key. Make sure you have a good handle on the intervals and basic chord constructions before moving onto the examples below, as you will need this knowledge to successfully complete the activity.

The term diatonic refers to notes that occur naturally in a specific major or minor scale or key. In most cases, accidentals (sharps and flats) are required to complete the given key, however, we will be thinking intervallically for these exercises so it is just as important to know the intervals that are used to create the chords as it is to know the notes that comprise them. If you are unsure of either notes or intervals, make sure you go back to our previous lessons and review the material before attempting the examples below. It is also a good idea to review the staff and notes on the neck as well.

The basic concept behind the diatonic 7ths is that we are building a chord on each consecutive note of a given scale according to the intervals that comprise that scale. Remember, chords are built in thirds so we will be using four notes to create each chord because a seventh chord contains a root, third, fifth, and seventh. We will, of course, be arpeggiating each chord by playing one note of the chord at a time from the root up to the seventh and then back down to the root again, since playing an actual chord on the bass is not generally practical due to the low range of the instrument.

Before we begin discussing the chords themselves let's go over the symbols that we will be using to denote the different chord qualities. First off, we are using Roman numerals to number the chords from one to seven, because there are seven notes in a scale – the root, second, third, fourth, fifth, sixth, and seventh. We are not including the octave because it is the same note name as the root and, therefore, marks the place where the chord sequence repeats. Chords that contain a major 3rd will be written as an uppercase Roman numeral. Chords that contain a minor 3rd will be written as a lowercase Roman numeral.

In regard to chord qualities, we will be employing various symbols to represent each of the different types of chords. A triangle will be used to represent a major chord. A minus sign will be used for minor chords. The plus symbol implies an augmented chord. A circle denotes a diminished chord. A circle with a diagonal line through its center indicates a half diminished, or minor 7th flat 5, chord. If you are unsure of how to construct any of these chords, make sure you revisit our lesson on chord qualities before moving ahead with this lesson, as you will need to know how to form each of the above chord types.

Our first set of diatonic 7ths are those of the major scale. The intervals comprising the major scale are the root, major 2nd, major 3rd, perfect 4th, perfect 5th, major 6th, and major 7th. Notice I have written them out in the key of C major, but the chord qualities will remain the same regardless of the key that they are played in, so make sure you take these examples through all of the major keys when you practice them. I would also like to add that this set of diatonic 7ths is the most common and widely used of the four sets we are going to study, so it would be beneficial to commit them to memory.

In example one, we see that the chord that is built on the root is called the one chord. There is a triangle between the letter C and the 7, which tells us that this chord is major. The two chord starts on the major 2nd of the major scale and is minor, as we can see by the minus sign between the letter D and the 7. Our three chord, built on the major 3rd of the major scale, is also minor. The four chord, which is built on the perfect 4th of the major scale, is major, like our one chord. The five chord, which is built on the perfect 5th of the major scale, is dominant. Chords that have a 7 after the letter but no symbol are always dominant. The six chord, built on the major 6th of the major scale, is minor like the two and three chords. The seven chord, built on the major 7th of the major scale, is half diminished, or minor 7th flat 5, as per the symbol between the letter B and the 7.

Example two illustrates the next set of diatonic 7ths, which are based on the natural minor scale. The construction of natural minor is root, major 2nd, minor 3rd, perfect 4th, perfect 5th, minor 6th, and minor 7th. If you compare this set to the last set you will see that the diatonic 7ths of natural minor are the same as that of the major scale beginning on the six chord. In other words, the one chord of natural minor is the six chord of major, the two chord of natural minor is the seven chord of major, the three chord of natural minor is the one chord of major, and so on.

The next set of diatonic 7ths are based on the harmonic minor scale. The harmonic minor scale is one note different than the natural minor scale in that it contains a major 7th instead of a minor 7th, making its construction root, major 2nd, minor 3rd, perfect 4th, perfect 5th, minor 6th, and major 7th. Although only one note has been altered, four chords will actually be affected by the change, as this note will appears in different parts of each of the four chords. Take note, every chord in the series is a different quality.

Let's take a look at example three below. The one chord is now minor with a major 7th, indicated by the minus sign with the triangle. The two chord, built on the major 2nd, is still half diminished. The three chord, which starts on the minor 3rd, is now augmented. (Technically, this chord is major 7th#5 because it contains a major 7th instead of a minor 7th.) The four chord, built on the perfect 4th is still minor. The five chord, beginning on the perfect 5th, is now dominant. The six chord, starting on the minor 6th, is still major. The seven chord, which now begins on the major 7th, is fully diminished.

Our last set of diatonic 7ths are based on the jazz minor scale. The jazz minor scale is constructed like the major scale with a lowered 3rd, making its construction root, major 2nd, minor 3rd, perfect 4th, perfect 5th, major 6th, and major 7th. Here again, simply changing one note in the scale will alter four of the seven chords in the series because that particular note appears at some point in each of the four chords.

Example four shows the diatonic 7ths of the jazz minor scale. The one chord is still minor with a major 7th. The two chord, built on the major 2nd, is now minor. The three chord, which starts on the minor 3rd, is still augmented. (Again, it is actually major 7th #5). The four chord, built on the perfect 4th, is now dominant. The five chord, which starts on the perfect 5th, is still dominant. The six chord, which is now built on the major 6th, is half diminished. The seven chord, built on the major 7th, is now half diminished. I think this set tends to be easier to remember than our last set because the four and five chords and six and seven chords are the same quality.

In addition to memorizing these diatonic 7ths make sure you practice them in every key. Simply knowing them is not the same thing as being able to apply them in an actual performance situation. Having the ability to instantly recall the pattern that chords follow in a given key will pay tremendous dividends in soloing and improvisational settings. In addition, thinking of chord progressions in terms of numbers as oppose to note names will make transposing songs to different keys much easier and faster. Until next time, stay passionate about music and never stop practicing!