The Crusade. Part 6: Diatonic Seventh Chords

author: JoshUrban date: 12/20/2007 category: general music
I like this
362
voted: 38
Oh wow. This sounds scintillating. Almost as fun as a day at the roller coasters with sea sick in-laws. Sorry, I must have drank too much sarcastic tea this morning. Hey, pay attention! Dig this! Do you understand the principles presented in the last lesson? Do you understand how to build triads (three note chords) from a scale, soldier? Are you ready to risk brain rot, serious headaches, and not watching reruns on TV, punk? Are You? (That tea must have had Drill Sergeant brew in it, too.) We'll be learning about four note chords built from a scale. But why so many notes, Santie Claus, why? asked Little Cindy Lou Who. Ah, the seventh chord. That slightly sophisticated cousin of the humble Major and minor chord, it's found in styles ranging from Jazz to Rock. Often as misunderstood as it is seen on chord charts, this four note assembly of notes is a great way to add some pizazz to your playing, and depth to your knowledge of theory. Read on, brave crusaders! What we'll be checking out in Part vi is how to harmonize the major scale in seventh chords. In plain English, this means: Building four note chords from the major scale, just like we did with triads (three note chords) in the last lesson. A C Major 7 Chord has the following tones: C E G B If we look at the C major scale: We see that C is the 1st note of the scale, E is the 3rd, G is the 5th. (Nothing new so far.) B is the 7th scale tone above C. Hence, if we build a chord using the notes C E G B, since B is seven scale tones above the root, C, we call it a C Major 7 chord. Next, let's look at what seventh chords live in a major scale (in other words, what chords that can be built from the scale tones.) A resident seventh chord would be said to be a diatonic chord, diatonic meaning relating to the scale (A very oversimplified definition, but it gets the job done.) The Formulas There's four types of seventh chords that can be derived from the Major scale, and it's related modes. Major 7: minor 7: Dominant 7: minor 7 (b5): {sometimes called a half diminished chord.} Here's how the intervals fall, folks. (For those just joining us, M3 means Major 3rd, and m3 signifies minor 3rd. See The Crusade - Part iii for more details.) M3 + m3 + M3 = Major 7 m3 + M3 + m3 = minor 7 M3 + m3 + m 3 = Dominant 7 (often just notated 7. If we play a G dominant 7 chord, we would write G7.) m3 + m3 + M3 = minor 5 (b5) M3 + M3 + M3 (Augmented triads) and m3 + m3 + m3 (fully diminished 7th) exist, but are not found in the confines of the Major scale and it's related modes. Of course, it goes without saying to learn about these chords, but for the purpose of this article, we'll skip these formulas for now. How The Chips Fall (Memorize This Pattern!) Using the same logic presented in The Crusade - Part V to build chords, we end up with this. The I and IV chords of any major scale are always Major 7 chords. The ii, iii, and vi chords of any major scale are always minor 7 chords. The V chord of any major scale is always a Dominant 7th chord. The vii chord of any major scale is always a minor7(b5) chord. Runnin' The Numbers For the C Major scale, we would end up with: C Major 7 D minor 7 E minor 7 F Major 7 G7 A minor 7 B minor 7 (b5) {read B minor seven, flat five.} This Major-minor-minor-Major-Dominant-minor-minor 7 (b5) sequence is always the same for any Major scale, no matter what fret, note, or planet you start it on. Why Let's take a closer look at just how we end up with these chords. Our scale: Starting on C, we know that the I chord is a Major 7 chord. We'll start by taking every other note until we end up with four notes (remember, a 7th chord has four notes, a triad has three.) We get: C E G B Our formula for a Major 7 chord is; M3 + m3 + M3. C to E is a Major 3rd. E to G is a minor 3rd. G to B is a Major 3rd. La dee da, it fits our formula for a Major 7th chord perfectly. We do the same for the remaining six chords. I outlined this process in a detailed manner in The Crusade - Part V, so if any of this isn't clicking, or you're unsure of how the next chords would be built, feel free to refer back to that article for reference. Conclusion
  • A seventh chord is a four note chord containing a note we start on (the root), a note a 3rd above that, a note a 5th above the root, and finally, a note a 7th above the root. (By the way, you might see a pattern here. How about a ninth chord? That would contain a five notes, the highest note being nine scale tones above the root.)
  • There's four types of seventh chords that can be built from the major scale and it's related modes: They are: Major 7, minor 7, Dominant 7, and minor 7 (b5). The minor7(b5) is sometimes called a half diminished seventh chord. (Where did the fully diminished 7th chord go? That's our m3 + m3 +m3 formula. However, this chord doesn't live in the major scale, and would be out of key with the scale.)
  • Seventh chords, containing four notes, are slightly more subtle and complex sounding than triads (three note chords.) Am I Wasting My Time? So you know how to build seventh chords from a major scale. Now what? In the next installment, we'll be checking out how to figure out the key of a song by looking at it's chords. The concepts presented in this article are necessary steps to understand how to analyze a chord progression. Stay tuned, it's gonna be fun, and you'll really start using this stuff - I promise! Keep on rockin, Happy Holidays, and I'll see you next time. Don't forget to check out my blog. Copyright 2008 Josh Urban - All Rights Reserved Josh Urban (photo) is a musician with a unique perspective on music. Always a thinker, he gains insight wherever he can find it, be it in the clubs as a working musician, busking on the city streets, or teaching in the classroom. A naturally enthusiastic fellow, Josh is always fired up about bringing the lessons he's learned to his readers. Maintaining a website, a blog, and a monthly newsletter, he aims to make musicians stop, think, and play with a little more intensity, integrity, and inspiration. You never know who's listening.
  • More JoshUrban columns:
    + The Modes Made Simple Music Theory 06/08/2012
    + Fire Your Slacker Band. Part V General Music 10/19/2010
    + Fire Your Slacker Band. Part IV General Music 10/12/2010
    + Fire Your Slacker Band. Part III General Music 10/05/2010
    + Fire Your Slacker Band. Part II General Music 09/29/2010
    + Fire Your Slacker Band! General Music 09/23/2010
    + view all
    Comments
    Your captcha is incorrect