Theory/Circle of 5th's question

[froglips]

OK, so I know that the Circle of 5th's is mainly for identifying the flats and sharps in each key, but I have a question about modes with reference to the circle of 5th's.

So, I am assuming that because you use the Ionian mode (WWHWWWH) pattern for the standard Circle of 5th's to find the flats and sharps in each key for that mode, that you would do the same thing for all other modes in order to find the flats and sharps in the keys of the other modes?

In other words, when starting with the key of C major to begin the circle of 5th's for another mode, do you just apply the different pattern for each mode to find the correct notes, flats, and sharps, for each key for that mode?

I hope that made sense.

If you play a C, and you make a series of perfect 5ths from C, you don't end up with the notes of the Ionian mode, you end up with the notes of the Lydian.

Example
C G D A E B F#

B to F# is a perfect 5th, B to F is a diminished 5th.

Just thought to point that out. If you cycle through the different notes in the pattern, you get this

Lydian - Ionian - Mixolydian - Dorian - Aeolian - Phrygian - Locrian

Then between Locrian and the Lydian you have a diminished 5th.

What was the question again?

[gavinspoon]

If you're just looking for a way to work out the key signatures, then there's no need for a new circle of 5ths for each mode as they use all the same key signatures,you just have to think about it a bit.

Each mode is already linked to a key signature because it's derived from a standard major scale in the first place.

So taking C as the example

C Ionian is the standard C major scale, and all the other modes derived from it share the same flats and sharps (as it's all the same notes) so in a way they are all just different shades or extensions of the same key. The modes of C being;

D Dorian
E Phrygian
F Lydian
G Mixolydian
A Aeolian
B Locrian

I think of it in terms of chords. i.e. D is the II chord of C, A is the II chord of G, E is the II chord of D etc. so for Dorian just go round the original circle of 5ths but using the root note of the II chord as the tonic. For Phrygian think of the III chord, Lydian the IV etc.

[Jake of Bass]

I think I understand what the OP is saying.

They're saying that if you start in D dorian, if you follow the CoF and go to A and play a Dorian mode, will you get the next diatonic key in the sequence. They just don't know they're actually asking this

froglips: you should learn the diatonic modes in relation to C major, the CoF and then translate what you've learned from the diatonic modes of C major into a new key. I'm assuming you can do both, hence your question in the first place.

So if you've learned that, you know the order of the diatonic modes from C major (ionian) goes like this:

C Ionian
D Dorian
E Phrygian
F Lydian
G Mixolydian
A Aeolian
B Locrian


It then stands to reason that if you move your ionian mode up a fifth, all the other modes must move up a fifth as well to be diatonically correct with the new key, which is G ionian.

So the sequence would then look like this:

G Ionian
A Dorian
B Phrygian
C Lydian
D Mixolydian
E Aeolian
F# Locrian


Make sense?