Music Theory for Poets #2

Ready for some more music theory?  Remember, this is for poets (non-poets welcome too, of course), so we’re making this as painless as possible!

When I left you last, we were just starting to think about the difference between major & minor chords.  In fact, we discovered a chord called a major 7 that’s a combination of a major chord & a minor chord—music can be pretty witchy that way. 

OK—most folks know do-re-mi-fa-sol-la-ti-do.  It’s a major scale—what makes it major?  Actually, there are a few considerations, but for today we’ll just consider the most basic: that’s the interval between do & mi.  If you can sing “do-mi” you are singing what musical types call a “major third.”  If you have a piano or keyboard around the house, play a C followed by an E a couple of notes above it—again, a major third.  A plain old major chord contains just three notes: do-mi-sol.  That’s it!  Here’s that major third:

  C major chord-C minor chord by rfrostbanjo

Perhaps you have a guitar around.  Actually, since you’ll just be using one string, it doesn’t even matter too much whether it’s in tune.  Pluck the low E string—confusingly enough, the “low E” is the string that’s closest to your nose when holding the guitar in any conventional manner.  The high E is the string closest to your toes.  So pluck that low E, then fret the E string on the fourth fret.  In case you’re curious, that’s a G#.  E.  G#.  Major third!  Here’s what it sounds like:

  Guitar major 3rd by rfrostbanjo

Now there are a few differences between a major & minor scale, but for today, let’s just worry about chords.  & I can tell you there’s only one note that’s different between a major chord & a minor chord!  It’s hard to explain using do-re-mi; because the difference would be that rather than singing “mi,” you’d be singing “mi-flat.”  So if you have a piano, strike the C, then strike the Eb a note & a half above it (it’s the black note to the left of E natural).  That’s a minor third:

  Piano Minor 3rd by rfrostbanjo

With your guitar, pluck the E string, then fret the third fret.  You’re playing an E, then a G.  Just a plain old G natural, not G# as you were before.  That’s a minor third.

  Guitar minor 3rd by rfrostbanjo

So the notes of a minor chord are “do-mi flat-sol.”  “Do & Sol” remain the same.  This can be expressed as a pattern of “whole steps” & “half steps,” but this is music theory for poets, so we won’t worry about that right now.  Suffice it to say that sol is the fifth tone of the scale—you can see that easily enough: do-re-mi-fa-sol.  If you’re still at your piano, you will find the “sol” for C is G.  If you play C-E-G simultaneously, you’re playing a C major chord.  If you play C-E flat-G simultaneously, you’re playing a C minor chord.

  C major chord-C minor chord by rfrostbanjo

Now back to the guitar.  We know that if E is “do,” then G sharp is “mi.”  If E is “do” & a G natural is played, it becomes minor.  The “sol” of E is B natural—that would on the 7th fret of the low E string (guitar players—the 7th fret is always the “sol” or fifth of the open string!—also true of banjos, ukes, bass guitars, mandolins, etc)  So E-G sharp-B is E major; E-G-B is E minor.

  Guitar E major E minor by rfrostbanjo

If you recall last time, I mentioned that a major 7 chord adds the tone “ti” from the major scale.  That makes sense because if you count to seven, you’ll see that “ti” is the seventh tone of do-re-mi.  Now it so happens that if you play a C major scale, you’ll hear that B natural is the “ti” note.  Now think about it: a C major 7 contains the notes C-E-G-B.  Think about the C major chord: C-E-G.  The E minor chord? E-G-B.  See how that works?

In the poem “How High the Moon,” I wrote:

 “a trailer truck on Highway 95, the glass slide whooshing guitar strings, a riff existing somewhere between the major & minor modes”

&

“the glass slide existing somewhere between the major & minor modes”

There are a number of guitar riffs, particularly associated with the blues—& therefore by extension to rock & jazz & even country that incorporate the ease with which the guitar can move back & forth between major & minor chords, especially in certain keys.  One of the simplest is this, in the key of E: 

  Guitar major minor strum riff by rfrostbanjo

Here are a few I particularly like in the key of D (with the bass string tuned down to D):

  Guitar drop D riffs by rfrostbanjo

Of course using a slide—which regular readers of Robert Frost’s Banjo know from my Monday Morning Blues series—enables the player to move between tones (& actually even in micro-tones of the established scale) without actually pressing down the strings.  So moving back between the major & minor thirds—again in the key of D, on a guitar tuned to an open major D chord (hey, you know what that means now), sounds like this:

  JH-D slide riffs by rfrostbanjo

That’s all for now.  Next time?  Extended chords!