Sometimes this stuff gets more complicated than it needs to be, and sort of runs away with its self. Do you ever wonder why so many music theory explanations start with C? Or "hey, lets learn the Cmaj scale!"? Why is that, and what are all these "modes"? What do we mean by "natural minor" anyways?
Start with C. Great. Ok, welcome to music theory 101. The reason we like "Cmaj" so much is because it is a seven note scale that is "natural", meaning, we have no sharps, and no flats: C D E F G A B.
(Simple rule with flats, sharps, and notes. We NEVER mix flats and sharps in any given scale, and we never use the same letter twice when describing a scale).
Back to that Cmaj scale. Ok, there's no sharps or flats, every note is natural. Now, lets count out the steps starting from C to D and so forth, and as you already know we get: W W H W W W H.
Ok, no revelation there, but the idea here is that ANY combination of seven notes that follows the pattern W W H W W W H will form a MAJ scale, even if it has sharps or flats, because its all based on the almighty Cmaj scale which is the "rosetta stone" of scale theory.
So what's with this "natural minor" thing? Ok, well lets go back to that Cmaj scale where are the notes are natural. Starting on C, we play through, and have a maj scale with all natural notes. C is the first note of the Cmaj scale. Because its the first note, C is the "tonic", and the root of the scale. When you say "I'm in the key of C" is means that the guitars, bass player, and keyboardist are all playing notes that want musically to resolve to C. That's the "root" of the scale. When you say "I'm in the key of Cmaj" it lets everyone know that the interval pattern your using is W W H W W W H. Everyone plays together and its all hunky dory.
But what if we start on a different note? "A" is the "relative minor" of "Cmaj". What does that mean? Well, if we take a look at our Cmaj scale "A" is the sixth note in the scale. So lets start with A, and count using the same intervals as Cmaj, but remember, we're starting on the sixth degree. It helps to see the patterns repeat, and laid next to each other:
Cmaj: W W H W W W H W W H W W W H W W H W W W H
A min: W W H W W W H W W H W W W H W W H W W W H W W H
(I've highlighted the two patterns by bolding them, and kept them apart just for the sake of visual clarity. In both cases, you would start the pattern at the first bold letter).
So for A natural minor, you can see we're really using the same "pattern" as Cmaj, but we just started at a different point.
This gives us W H W W H W W. Also, because we're using the same notes as the Cmaj scale, just in a different order, the A "natural" minor scale contains no sharps, and no flats. Because of this, any pattern of notes used to form a seven note scale that follows the interval pattern of W H W W H W W will be a "natural minor scale".
So now "A" is the tonic. Everything will want to resolve to A. Seems odd, but its all about that root note. If you get a chance, try playing the Cmaj scale over a C bass note or Cmaj chord. Come up with a little riff, but stay in the Cmaj scale. Now change the bass note to A or play over an A minor chord. Without having changed your riff, it will sound like you're playing in Amin, especially if you now resolve that riff to A, emphasizing A as the root note.
This is what modes are. Just different scales that are derived from starting the interval count at different points. There is one "mode" for each note of the seven note scale. Because they are derived from the Cmaj scale which has no sharps or flats, each mode will have one key that also contains no sharps or flats. A natural minor, derived from counting the intervals starting on the sixth degree is one such mode. D Dorian is another such mode. It is derived by counting starting at the second interval and also has no sharps or flats.
Hope that all makes sense, I know its a lot to get a handle on, but once you get the idea of how we come up with different scales, it helps in the general understanding of things. Harmonic minor and Melodic minor scales are different beasts in themselves, but the above should get you understanding scales and intervals.
Last edited by Slipin Lizard : 03-07-2013 at 10:41 PM.