Music Theory: Chord and Scale Application

by Guitarslinger124 (Nov 03, 2011)

Music Theory: Part V - Chord and Scale Application

An Overview

In this lesson, I will explain some general rules for figuring out which scales to use when constructing a solo over a chord progression and which chords to use under a set harmony. This lesson will build off all of the previous Music Theory lessons that I have posted, so it would be wise to read and understand them, prior to reading this lesson.

Getting started

First, let's get some names out of the way.

Your modes:

(The numbers are the degrees)

Nut 1st 3rd 5th 7th 9th 12th
Ionian/Major ||:(1)| |(2)| |(3)|(4)| |(5)| |(6)| |(7)|
Dorian ||:(2)| |(3)|(4)| |(5)| |(6)| |(7)|(1)| |
Phrygian ||:(3)|(4)| |(5)| |(6)| |(7)|(1)| |(2)| |
Lydian ||:(4)| |(5)| |(6)| |(7)|(1)| |(2)| |(3)|
Mixolydian ||:(5)| |(6)| |(7)|(1)| |(2)| |(3)|(4)| |
Aeolian/Natural Minor ||:(6)| |(7)|(1)| |(2)| |(3)|(4)| |(5)| |
Locrian ||:(7)|(1)| |(2)| |(3)|(4)| |(5)| |(6)| |

Some useful chords:

Nut 1st 3rd 5th 7th 9th 12th
Major Seven ||:(1)| | | |(3)| | |(5)| | | |(7)|
Dominant Seven (b7th) ||:(1)| | | |(3)| | |(5)| | |(7)| |
Minor Seven (b3rd and b7th) ||:(1)| | |(3)| | | |(5)| | |(7)| |
Minor Seven Flat Five (b3rd, b5th, b7th) ||:(1)| | |(3)| | |(5)| | | |(7)| |
Diminished Seven (b3rd, b5th, bb7th) ||:(1)| | |(3)| | |(5)| | |(7)| | |

Putting one and one together

Right, so there is a the old saying, "If it sounds good, it is good."

That is all good and dandy if you know what sounds good. If you don't, you are just as lost. That being said, there is always more than one option when deciding on what scale to use over a chord or progression. More to the point, I've come up with a simple excersise to help a player actually learn what sounds good and what doesn't.

Grab a pen and piece of paper. Pick a chord, any chord, but just one chord. Record yourself playing that one chord over and over. Or just once or twice and loop it. Next pick five modes and, don't solo per say because you want to really hear what you are doing, play them over your one chord. Play them one after the other. Or play all the modes in every key. But play them so you can clearly hear what they sound like. Now write down, and this is why I said pick five, what each one sounds like over that chord. I.e. "good", "bad", "cool sounding", "sad sounding", whatever. Now pick two chords and repeat the process. Except this time you can experiment a little. Play the chords however you'd like. As arppeggios or whatever you want. Play the same scales over just your two chords and write down what it sounds like. This time however, pay close attention to how two chords sounds different under the same scale as one chord does. Or how a particular mode is more suited for a particar note in one of the chords.

The goal of this is to hopefully help you understand exactly what effect particular chords and scales have on each when played in conjunction with one another. Now you will no longer have to waste time guessing and checking when all you really want to do is record. You will now know what a certain scale will sound like, when played over a certain chord or even more specific, what certain intervals will sound like when played together as a harmony or when played seperate as melodies.


Here is a simple table to help you put scales and chords together. I'm not going to list anything super complex so don't worry if you are a beginner. This is basically just a quick reference guide. This is far from a list of finite values, just a starting place.

Mode Triad 7th

[dot]Ionian | Maj | Maj7 |
[dot]Dorian | min | min7 |
[dot]Phrygian | min | min7 |
[dot]Lydian | Maj | Maj7 |
[dot]Mixolydian | Maj | 7 |
[dot]Aeolian | min | min7 |
[dot]Locrian | dim | min7b5 |

Like I said above, there is never a finite solution to the eternal question of "What do I play with this?". And if you take a look at the chart, you can clearly see that if you were to play a Maj7 chord, you chould play either the Ionian, or Lyidian scales. Or if you were to play a minor chord, you would be free to use the Dorian, Phrygian or Aeolian scales.


Now you should be asking, "OK, you told us about individual chords, but what about already formed prgressions?"

I know that JazzMaverick covered this topic in her lesson, Keys, Scales and Their Note Values, so I would also recommend checking that out.

Also note that at this point you should make sure you understand my lesson, Music Theory - Turning Your Scales into Chords.

There is a untold rule of thumb, that the resolving chord in a progression will determine the tonality.

If you can wrap your head around that, then wrap it around this: match the resolving chord. Don't worry about the rest of the progression, unless you are dealing with some wierd stuff. Focus on the resolution. So, match the resolving chord to the corrosponding scale.

Here is two quick reference tables:

I | | ii | | iii | | IV | | V | | vi | | vii | | VIII
| W | | W | | H | | W | | W | | W | | H |
maj | | min | | min | | maj | | maj | | min | | dim | | maj

Scale Chord
[dot]Ionian - I
[dot]Dorian - ii
[dot]Phrygian - iii
[dot]Lydian - IV
[dot]Mixolydian - V
[dot]Aeolian - vi
[dot]Locrian - vii

Let's build a simple progression using only major chords in the key of C.

I - IV - V - I
Cmaj Fmaj Gmaj Cmaj

So your resolving chord is Cmaj. More importantly, your resolving chord is the I chord. Looking at the reference chart, the I chord matches with the Ionian scale. Therefore, the C Ionian scale would be the "best" scale to use. And I use the word "best" loosely. There obviously is no best scale.

Now lets make a progression, again in the key of C, using minor chords.

ii - iii - vi - ii
Dmin Emin Amin Dmin

Again, looking at the resolving chord. It is Dmin, which is the ii chord. You see that the ii chord matches with the Dorian scale. So the D Dorian scale would be a safe bet. Ofcourse, if you scroll back up the page and look at the Mode-Triad-7th chart, you would notice that you could also play E Phrygian or A Aeolian scales here.

Wrapping up

This whole lesson has involved fairly simply ideas compounded on top of each other. What happens when it gets more complex? Just remember that almost everything in music can be broken down and examined at the micro level. Don't get intimidated by not knowing or not understanding something. Just break things you are having trouble with into smaller, easier to deal with sections.

I hope this lesson helped answer alot of questions about application and "the right chord/scale" to play and so on.

Rock on!