I need help understanding chord progressions

[The LUE volta]

One thing i dont understand about chord progressions, is the chords derived from a scale.

I know that for an ionian mode the chords are I = maj II = min III = min IV = maj V = dom VI = min VII = dim.

One thing i dont understand though is how to go about devising the chords for say a mixolydian or aeolian mode, any help would be greatly appreciated.

[Trigger_003]

Well if you know how modes work already scale wise, it's simple. It's just a case of reordering the diatonic chords in much the same way you would reorder the notes of the scale.
For instance, aeolian starts on the sixth degree of the major scale... In Cmaj, that's A. So instead of going CDEFGAB, your scale now goes ABCDEFG.

The diatonic (scale relative) triads (chords with the first, third and fifth degrees) for C major are I = CMaj, II = Dm, III = Em, IV = FMaj, V = GMaj VI = Am and VII = Bdim. The sixth chord (whose tonic, as we know, is the 6th note in the scale of Cmaj) is in bold.

To construct the chords for... A natural minor (A aeolian), you simply take the chords used in Cmaj, but instead of starting the process with Cmaj, start it with the Am:
I = Am, II = Bdim, III = CMaj, IV = Dm, V = Em, VI = FMaj, VII = GMaj.

And you just do that kind of process with whichever mode you're using. Hope that helps :thumb:

[The LUE volta]

Well if you know how modes work already scale wise, it's simple. It's just a case of reordering the diatonic chords in much the same way you would reorder the notes of the scale.
For instance, aeolian starts on the sixth degree of the major scale... In Cmaj, that's A. So instead of going CDEFGAB, your scale now goes ABCDEFG.

The diatonic (scale relative) triads (chords with the first, third and fifth degrees) for C major are I = CMaj, II = Dm, III = Em, IV = FMaj, V = GMaj VI = Am and VII = Bdim. The sixth chord (whose tonic, as we know, is the 6th note in the scale of Cmaj) is in bold.

To construct the chords for... A natural minor (A aeolian), you simply take the chords used in Cmaj, but instead of starting the process with Cmaj, start it with the Am:
I = Am, II = Bdim, III = CMaj, IV = Dm, V = Em, VI = FMaj, VII = GMaj.

And you just do that kind of process with whichever mode you're using. Hope that helps :thumb:


Damn that is exactly what i thought it should be like but my guitar teacher gave me a sheet which contradicted that, maybe it was just a typo or something.

anyway thanks for the help.

[Trigger_003]

Did they say min, dim, Aug, min, Maj, Maj, dim, min?

Because that's the pattern for the harmonic minor scale, which they may have given you, having labelled it as simply being the diatonic triads for a "minor scale"...

[The LUE volta]

Did they say min, dim, Aug, min, Maj, Maj, dim, min?

Because that's the pattern for the harmonic minor scale, which they may have given you, having labelled it as simply being the diatonic triads for a "minor scale"...

No no it was just me getting confused and messing up.

But you remind me of another question i want to ask, how would youu go about finding out the chord progression of an altered scale like melodic or harmonic minor?

[Trigger_003]

Alright.

Well let's cover something first... it should make all of this a whole heap easier.
To construct the diatonic traids for any scale, there's a quite simple process (well it is if you can use notation to do this. It's a bit harder without it, but still okay) you can follow.

Simply take the actual scale and throw on two generic thirds to each degree... e.g.

For Cmaj: http://www.tdknights.com/trea/files/traidsmaj.JPG

The first bar shows the notes of the major scale. The second bar shows each of those notes with a third stacked on top of them. Then in the third bar you've also got the fifth on there as well.

Correct me if I'm wrong, but I assume I'm not telling you anything new when I say that, looking at the first chord (which we know to be Cmaj), we can tell that it is a major chord because it is constructed with a tonic, major third and perfect 5th.

Likewise, we can tell that the second chord in Cmaj, Dmin, is minor because it is the same as a major chord but with a flattened (or minor) third.

And so forth across the scale (diminished, as I also assume you know, is constructed with 1 b3 b5).
Eventually you will come up with the formula MmmMMmd.

Take a natural minor (aeolian) scale and do the same thing. Analyse the resulting triads and you will find your formula is dMmmMMm.

Then take a harmonic minor and repeat the process. Now, the harmonic minor scale is the same as natural minor, except the 6th degree of the scale is raised by a semitone. In the case of A harmonic minor, your notes will now be A,B,C,D,E,F,G#.

Because there's a G# in there now instead of a G, you're going to have a different set of chords; using a G# where ever there was a G in the chords used for your A natural minor. This will result in the third triad (C being the tonic of this particular triad) having a sharp fifth.

In case you don't know, augmented chords are made up of 1 3 #5. As I just said, the chord we're constructing for C has a sharp fifth (G# instead of a G)... i.e. it is an augmented chord.

So once you've worked out all the chords for that scale, you should have the formula: min, dim, Aug, min, Maj, Maj, dim, min for any harmonic minor.

And you can use that kind of process for working out your other scales in much the same way.

Btw, melodic minor is (for A melodic minor) A,B,C,D,E,F#,G# ascending and A,B,C,D,E,F,G decending. Say if you're having trouble working out the triads for that.

Hope that makes sense :).

[Trigger_003]

Bump?