Modes 101

Guitar players always seem to want to one up the other guy by playing in modes (lets be honest, most girls don't care).  We arrogantly advertise that we know what is going on even if we don't have a clue.  Then we run home to search for a comprehensive guide to modes on Google but often the explanations are nearly impossible to understand.  I'm here to try and save you.  Here is the most basic way I can explain what modes are.

If we take the C major scale we find that the notes are arranged like this:
C D E F G A B C

We can break that scale down to a series of half and whole steps like this:

C - D is a whole step, also called a whole tone

D - E is a whole step,

E - F is a half step, also called a semitone

F - G is a whole step 

G - A is a whole step

A - B is a whole step 

B - C is a half step.  

By looking at what makes up a scale, we should be able to see a pattern emerge. In the case of this major scale, we see this pattern:  Whole step, Whole step, Half step, Whole step, Whole step, Whole step, Half step.  Now here is where the fun comes in.  The different modes that we use are just this pattern beginning and ending at a different point.  Let me illustrate.

Here is the pattern for two octaves of a major scale, also known as the Ionian mode: (W stands for Whole step and H stands for Half step)

W W H W W W H - W W H W W W 

If we begin this seven part pattern on the second degree we get something that goes like this:

W H W W W H W  (starting on the second W of the above pattern)

This is called the Dorian mode.  This is a very neat minor sounding mode to play in.  Think Halo splash screen...

If we start on the first H of the pattern we get this:

H W W W H W W 

This is the phrygian mode.

The Lydian mode starts on the next degree:
W W W H W W H  This one sounds a little like a major on the bottom end of the scale and a little minor on the top

The Mixolydian mode begins like a major scale and is major all almost the way through.

W W H W W H W

The Aeolian mode uses this pattern:

W H W W H W W  This one will sound familiar to most guitar players since it is also known as the natural minor scale and the majority of rock and blues is built on this mode.  The seventh degree of this scale is often raised in order to strengthen the pull back to the tonic pitch.

This last pattern is an interesting one.  Because it has two naturally occurring tritones in it, many music theorists consider it to not be a mode at all, however it is almost indispensable for a jazz player.  Here is the Locrian mode:

H W W H W W W

An Irish guy (and one of the better human beings around) told me a little saying to remember the order of the modes and it goes like this:

I          Don't    Play       Like     Most           Average Lads

Ionian Dorian Phrygian Lydian Mixolydian Aeolian Lochrian

And that's that!  Good Luck!

Theory in Practice

So here is something that twisted my noodle.
One of my classes that I take at school is a studio class.  That means that I have one on one music lessons on the piano.  My instructor is one of my favourite people at the school and I have recently been informed that she knows every piece on the planet.  Wow.  Anyway thats not what twisted my noodle.  I was working on some technique with my instructor (no good), when I discovered that there are only 3 diminished seventh chords ever.  EVER!  This is how it works:
A diminished seventh chord is made up of three minor thirds.  Because that is the case, it turns out that the root position of that chord is also the first inversion of the diminished seventh chord that begins a minor third down.  At the same time it also is the second inversion of the chord starting 2 minor thirds (or a diminished fifth) below.  At the same time as the chord is being those three cords, it also happens to be the third inversion of the chord that starts a minor third below that!!  Wow!  So when one chord actually equals four chords, and there are 12 keys in our tonal system, then only three of these chords are needed to cover all of the diminished sevenths of every key!  And the coolest thing is, that when you are playing these things on a piano, the fingering never changes!  Guitar will be much the same *if you want to change keys, just slide up the neck right?  Anyway I was thinking and from a composition standpoint, these chords could be used as a really nice pivot chord when you want to change keys and want to be a little sneaky about it.
Well, thats enough nerdy raving for today.