Basic Music Theory for Guitarists

Brian · Pit Bull Joined: 26 Aug 2003 Posts: 373

I wrote this in another thread but it really should be in here. I'm self taught and I hold someone with F1's background in high regard. As I mentioned there I'd invite F1; pls correct any errors and add any nuggets you have.

When I took music theory it seemed a very confusing concept of stacked intervals; major and minor 3rds as I recall. Then I figured out that that it was a few rules based on the simple scale
do, re, mi, fa, so, la, ti, do
root, 2nd, 3rd, 4th, 5th, 6th, 7th, octave,
and octave, 9th (or octave 2nd), (octave 3rd), 11th (or octave 4th), (octave 5th), 13th (or octave 6th)

the very basic rules

* Basic chord = triad
* triad = root, 3rd, 5th
* minor = b 3rd (flat 3rd)
* Major 7th = natural 7th
* 7th or dominant 7th = b 7th
* augmented = # (sharp) 5th
* diminished = b 3rd & b 5th
* sus (suspended) is playing the 4th instead of the the 3rd
* extensions like 2nd, 6th, 7th, etc are just added to the basic triad

octave extensions are supposed to be stacked but I feel since a guitarist only has 1 hand and 6 strings to voice the chords, it's less important. For example the 9th chord includes a 7th (dom or b 7th). If the 7th is not played it's really an "add9", but it gets the essence of the extension.

Now you can forget all this stuff and to quote brother ACf Laughing

Ferrari 1 · Posted: Wed Feb 25, 2004 1:20 pm Post subject:

Brian,
This is right on, and I particularly like the way you have simplified it for the benefit of the reader. Usually, people ( like me) tend to over complicate things because we know enough to be dangerous. It's the
"one thing leads to another thing" syndrome. That's one reason I am not a good teacher. I know my limitations. When I graduated Berklee, they invited me to stay on staff as a professor. I had to say no, because I know that is not a gift of mine. You have the gift.

This is great, and I really think members who don't know this, should print your post and keep it with their guitar, so they can practice this theory. What you have posted is the foundation for all the other "stuff" I had to learn to get my music degree.

Great, great post, and I encourage beginners and intermediate theory students to print it and refer to it.

Keep the instructional posts coming. It's good for everyone. Very Happy

Blessings,
Ferrari 1

Steve · Posted: Wed Feb 25, 2004 4:53 pm Post subject:

You're right on, Brian,

And now for some Jazz theory:

Make those chords SEVENTH chords, and you have a harmonized seventh scale, which is basic Jazz theory:

Lets do it in the key of F:

I - Fmaj7 (in the first position - "I")
ii - Gmin7 - III
iii - Amin7 - V
IV - Bbmaj7 - VI
V- C dominant 7 (C7) - VIII
vi - Dmin7 - X
vii - Emin7b5 (AKA E half-diminished 7) IX

Play them in order as a scale. This is how Westerm Pop music is put together.
The "modes" are assigned to the scale steps in the same order. You can play the chord, then the mode over two octaves up and back down, then the chord again.
This is how I learned modern music theory in College, and makes playing Contemporary Worship music less foreboding.

Brian · Pit Bull Joined: 26 Aug 2003 Posts: 373

Thanks for the kind words guys.

quackzed · Not So Newbie Joined: 20 Jan 2007 Posts: 9

an Emin7b5 is spelled E(root)G(flat3rd-minor3rd)Bb(flat 5th)and D(flat 7)
...just a regular minor 7 with a flattened 5!
an E DIM 7 is diminished, so it actually has a bb7.. a double flatted 7th
so it's almost the same... E(root)G(b3)Bb(flat 5)and Db(bb7, or double flatted seventh)
notice how in the e dim 7 chord all the notes are a minor 3rd(3 frets) apart
E(f)(f#)G(g#)(a)Bb(B)(c)Db!
also notice that an e dim 7 has the same notes as...
G dim 7 (G,Bb,Db,E)
Bb dim 7 (Bb,Db,E,G)
and Db dim 7 (Db,E,G,Bb)
thats whats so cool about diminished chords and scales, they are the same shape in each inversion, so you can slide em up and down a minor 3rd(3 frets) and have a different inversion of the same chord(same notes)
this is what gives diminished chords and scales that ambiguous quality, there is no 'real' relationship to the major scale, so there is no way for your ear to tell which key they belong to; 2 of the notes are 'out' of key no matter which key your in... so a minor7b5 is usually a ii chord in a minor key (ii,V,i) Bm7b5,E7,Am7 a common jazz turnaround in a minor key
and a dim7 is usually the vii chord.. that leads back to the I chord and adds extra 'tention' or ambiguity...

maplebaby · Tadpole Joined: 22 Mar 2008 Posts: 15

great info. thanks for posting! I will use this with some of my students.