adding the seventh
Do you use chords with an added seventh in the music you create? Like C 7 or G 7? What happens to the harmony of triads when we add the seventh? In evolving the basic three note triad by adding the seventh, are we crossing a theoretical line that can significantly impact the music we create, and are these theoretical boundaries stylistically definable? As we move out of the realm of traditional American folk music and it's reliance on the major and minor triad, is it in adding the 7th degree to these triads that create the myriad of different styles based on this folk music, music such as folk rock, blues rock, country rock etc.? And although blues, rock, country and jazz players often use triads in creating their magic, is adding the seventh degree to the basic harmonic colors what originally helped to define these styles? Compare the following two bass lines. Adding the 7th. Example 1.
Here the transition basic from a folk to the blues / rock quality in the above idea? Once this transition is made, our palettes can expand dramatically. How? Why? A potentially key theoretical aspect emerges by adding the seventh chord degree to a triad, allowing us to define a chord based on the quality of it's third and seventh degree. This enables the theorist to place virtually any of chord into one of three chord types or chord families. This homogenization of virtually any chord into one of the three categories can help to simplify learning the theory of chords for the emerging creative artist. This categorization of a chord by type can also help to determine various groups of pitches from which we can create our melodic ideas, over any given chord as defined by it's family. Really? Yep.
With this in mind, let's review the four different kinds of basic triads and then simply add the most common seventh degree normally associated with each chord. Here are the four basic triads represented by two different sized blocks, denoting the major and minor third, the two important intervals used in constructing tertian harmony. Example 2.
Using the pitch C for the root or fundamental, let's spell out each of the triads. Example 2a.
Cool with spelling triads? To add the 7th to each triad, we simply create the scale / arpeggio associated with each triad and locate the 7th degree, then stack it above the three notes of the triad. Thus the principles of scale / arpeggio / chord emerge.
Adding the seventh chord degree to major triads can be easily achieved from the major scale grouping of pitches. Here is the the major scale color and it's arpeggio built from the root C. Example 3.
From the above chart we can see the emergence of the 7th chord degree above the major triad. Players commonly term this chord a "major 7th chord" and it provides us with the first of our three chord types. Compare the major triad, the major 7th chord and their arpeggios. Example 3a.
The major 7th chord is rarely used in the various blues and rock stylings but is an integral color of the jazz and pop languages. Compare the intervals used to create the major triad and the major 7th chord. Example 3b.
From the above diagram, we can see that in creating the major 7th chord, we simply include the next diatonic pitch in the arpeggio, which adds another major third to our chord. Can we continue to extend our major 7th chord type with other diatonic pitches of the arpeggio? Of course we can, but you knew that right? Which interval will we add, a major or minor third? Click color tones / major 7th chords to explore.
Is there another quality of seventh that we can add to a major triad? You betcha, the blue or minor seventh. By doing this we create the second type of chord type, the dominant family of chords. Where does the dominant seventh chord diatonically come from? Well, dominant harmony is built on the fifth scale degree of our chosen melodic resource n'est pas? So, what pitch is C the fifth scale degree of? Right, the key of F major. Let's respell our chart from example 3 above using the pitches of F major and find it's dominant seventh chord. Example 4.
From the above chart we can spell the pitches of the C dominant seventh chord as created from the pitches of the key of F major. Compare the sounds and arpeggios of the major 7th and dominant 7th color tones built upon the root C. Example 4a.
Pretty distinctive eh? These are the two of the three big chordal components of American music. Perhaps you recognize the dominant color as being one essential component of American blues music? Compare the intervals of the major triad, major 7th and dominant 7th configurations. Example 4b.
Is the dominant color unique in that it stacks two minor thirds consecutively? Yes it is, this basic structure defines the dominant 7th chord quality. Cool so far? Any other qualities of sevenths generally associated with the major triad? Nope.
The second triad from example 1 above is the augmented triad. Let's add the most commonly used seventh quality to this distinctive color. Due to it's relative instability, the augmented chordal color is usually associated with dominant type chords of a resolving nature. Thus, using the pitch C as the root, we can extract this non-diatonic dominant color from the key of F major. C being the dominant pitch or fifth scale degree in the key of F major. Here is our chord spelling chart. Example 5.
We can see from the above chart that by simply raising the fifth ( + 5 ) of the C dominant 7th chord by half step, we "augment" the triad. To this augmented triad we simply add the diatonic seventh. Compare these two colors. Example 5a.
Hear the difference? Same 7th, different triad. A reasonably rare color indeed in the more basic styles of American music, the C 7 + 5 chord is oftentimes found in songs written in the minor tonality. A popular choice in American blues, in both the minor and major tonalities, we often hear the V 7 + 5 color as a hauntingly beautiful introduction. And of course, this augmented 7th color is essential on the jazz musicians palette of colors.
The third triad of example 1 is the all important minor triad configuration. To add the seventh to this chord we can simply obtain the correct pitch from the natural minor scale. Using C as our tonic pitch, here is a chart spelling out the pitches of the C natural minor scale and it's arpeggio. Example 6.
From the above chart we can see the creation of the minor 7th chord, the third and last of our chord types or families of chords. Compare the minor triad and the minor 7th chord. Example 6a.
Sound familiar? Both are very common colors in most styles of American music. Here are the intervals used to create these two important colors. Example 6b.
From the above illustration, we see the addition of a minor third interval to the minor triad to create the minor 7th chord. Can we diatonically extend this chord further up into the arpeggio? What size third do you think we will add next, major or minor? Is there a symmetrical relationship to the extending of the minor 7th chord type? Click color tones / minor 7th chords to explore.
Is there another quality of seventh that can be used with a minor triad? Do we ever use a major 7th with a minor triad? Yes we do. Although not all that common in the literature, this combination of minor triad and major 7th creates a rather unique sounding chord which is oftentimes used in the minor tonality. Commonly referred to as a "minor / major 7th", here is a chart spelling out the pitches. Example 6c.
We can see from the above chart that we have raised the seventh chord degree by half step. Compare the sound of the minor 7th and the minor / major 7th colors. Example 6d.
New minor color for you? Usable in the tunes you are currently playing? Perhaps the most common place we find this motion is in the following chord progression. Example 6e.
Variations on this last "passing seventh" idea? A few. Where can we diatonically create these unique combination of minor tonal colors? Perhaps from either the harmonic minor or melodic minor grouping of pitches? Ya hip? Do we have to be able to always diatonically create the colors we use? Nope. But being able to do so opens up the theory to the "what if" questions.
The last triad from example 2 above is the diminished triad. Do we ever add a seventh to this configuration? Well, of course, but you knew that right? Interestingly, like the vanilla minor triad, there are two common ways to extend the diatonic diminished triad, one which is diatonic, the second non-diatonic, which creates some interesting possibilities due to it's perfectly symmetrical construction. Really? Well, depends on your artistic directions I guess. Anyway, in "organically" creating these two possibilities within equal temper, we get the chance to really run the theory from the start. Here goes.
In diatonically extending the diminished triad we create what is commonly termed among players as the minor seventh flat five chord / ii min 7 b5 or simply half diminished. Rarely if ever used as a tonal center or tonic, the minor 7 b5 color is most often a passing chord. We can diatonically locate this chord from seventh degree of the major scale. To remain consistent with the above examples, let's build this half diminished color from the root C. The pitch C being the seventh degree or leading tone of the key of Db major, here is our spelling chart of the pitches of the Db major scale and it's arpeggio. Example 7.
From the above chart, we can see the flatted fifth pitch Gb within the chord, while the 7th is the interval of a minor 7th above the root, thus half diminished. Compare the minor 7 and the minor 7 b5 colors. Example 7a.
Cool sound eh? We often find the minor 7 b5 chord as a passing chord just prior to the tonic in both the minor and major tonalities. Example 7b.
From the above idea, we see the minor 7 b5 color basically functioning as a passing Two chord, i.e., built on the 2nd degree of the tonic it resolves towards, which in the last idea is Bb. Compare the intervals of the two colors above. Example 7c.
Which family of chords does the minor 7b5 belong in? Good question, to which there is not really a hard and fast answer. Some say poetatoe, some say patatoe. Right? Suffice at this juncture to simply say that the half diminished chord is within the minor 7th family, if only because it usually functions as a passing Two type chord. Click here for further examination of this potentially important half diminished color.
The second common way to add the seventh chord degree to the diminished triad is to simply add another minor third to the already diminished triad. Example 7d.
Aurally compare the half diminished or minor 7 b5 color to the fully diminished 7th chord. Example 7e.
Close in sound but different eh? Potentially two distinct colors with unique properties unto themselves. Can we diatonically create this color from one of our scale groups? Yes we can, actually from three different scale groups. From the symmetrical chromatic scale, from which all and any group of pitches can be diatonically created. From the symmetrical diminished scale and from the seventh degree of the harmonic minor scale. Thinking harmonic minor, C is the root of our chord, what harmonic minor scale the pitch C the seventh degree of? Right, Db harmonic minor. Here is the spelling chart. Example 7f.
Look familiar? Basically stacking minor thirds from the root. In root position, we commonly find this fully diminished chord as a passing chord. Example 7g.
The above idea simply places the fully diminished seventh chord as a passing chord between One and Two in the major tonality, we follow this with the Five chord, creating a common harmonic chord progression. Players commonly call this positioning of the diminished color as the sharp One diminished chord / # i dim 7.
We can also view the fully diminished seventh as part of a Five 7 b9 chord, the root of the diminished chord being the third of the Five chord, thus a C fully diminished 7th chord within the Ab 7b9 dominant 7th chord. Example 7h.
The above idea is a very common jazz harmonic motion, the essential Two / Five / One chord progression. We can also use this V 7b9 color to move into the minor tonality. Here we pair it with the passing minor 7 b5 chord and move into the minor tonality. Example7i.
Holding the common tone Bbb ( A ) in the lead of the Two and Five chords as done in the above idea is a common way to voice these colors, the common tone helping to glue things together. The fully diminished chord is a rather unique color, with some interesting properties. Click here to continue this line of thinking.
Other ways to add the seventh degree to the diminished triad? Nope, that's about all. What's next? How about putting these colors into common harmonic motions?
"Music is your own experience, your own thoughts, your wisdom. If you don't live it, it won't come out of your horn. They teach you there's a boundary line to music. But, man, there's no boundary line to art."