Music Theory

[Tarser]

The scale of C Major has modes built on each note. Dorian, phrygian, lydian, mixolydian, aeolian and locrian. The aeolian is also known as the 'natural minor' - I understand that. If you alter the 7th note of aeolian, you get an 'un-natural' minor - the harmonic minor. My confusion is this....why is the aeolian the 'natural minor' when there are other minor modes build from the C Major scale too? Dorian is a minor mode, so is phrygian. Thanks.

[Zacs-Master]

This might help:
http://music.stackexchange.com/questions/13960/why-is-the-aeolian-mode-the-minor-scale

[Tarser]

Thanks Zacs, I read through it and it seems the poster had the exact same question as me. I don't really think that anyone gave a really satisfactory answer though! So like him, I'm still a bit baffled.

[The Builder]

Minor scales are a whole different can of worms, Tarser. In Jazz, we use dorian; harmonic; phrygian minor scales all the time ......... and a few others too.

Maybe, to answer your question in a simple way ...........

Take C major - all the white notes - key signature is No sharps/No flats.

Take A Minor - same as above. They are "relative".

I guess it's called the Natural Minor because it has a key signature in which the music is notated.

The other Minors do not.

[Tarser]

Thanks 'Builder' man, I completely get it that the aeolian or natural minor scale is the RELATIVE minor of the Major scale and that they share the same key signature. (I understand that the harmonic min is simply an altered 7th degree so it's no longer 'naturally' found in the major scale). But the question remains - there are other minor modes created from, say C Major, so what makes the aeolian mode so special that it's the one that shares the key sig with the major scale? E.g, 'D' Dorian is minor and has all the natural notes of C Major, so why isn't this mode the relative/natural minor of the major scale?

[Tarser]

Again, just posing the question sets off unconscious processes. I think the answer has pooped into my head! For the benefit of anyone else with the same question, here's what I think the answer is....

The aeolian can be converted to a harmonic min by sharpening the 7th note. If you do this for Dorian, Phrygian or Locrian (the other min modes) you don't get a harmonic min. In D Dorian, for example, to get D harmonic min, you have to sharpen the C (7th note) and also flatten the B (6th note). Here's the answer - you have D harmonic min but this is doesn't belong anywhere in C Major. The B flat is shows you that it's the relative minor of F Major. Same process for th eother min modes....

[The Builder]

I think you've got nearer to it than I could, Tarser. That sounds fine. It's still underlined by the fact that the Aeolian is the Natural simply because it has a key signature (the same as the relative Major.)

This would make the other Minors kind of .............. er ......... UnNatural!