I've put it her just to keep for copy/paste purposes. Feel free to have a read anyways.
----------------------------------
Three Forms of Using Modes
1. The Traditional Form of Modes
The least recognised (on the internet anyway) form of modes is actually
their origins, predating major and minor scales and keys. The most
important thing about modes in this fashion is that they are in a
separate realm of tonality. Whilst there is a tonic/chord that they
resolve to, the pull to them is nowhere near as strong as a song in a
major or minor key. To maintain the ambiguous feel of a mode,
accidentals cannot be used as they'll hint at a stronger resolution, and
the chord structure cannot be too complex, as this will definately pull
the progression back to tonality.
To illustrate this, most people will say "play a one chord vamp, and
solo with the mode over it". The student will then play over it and go
"wow, that sounds crazy". Then they take it home and not understanding
it completely will profess they now know modes and justify it using the
dumbed down CST method, which will be described below.
I actually like to demonstrate it in a different way, when they're
ready. Play an i - ii vamp, just the chords. Where does it resolve to?
Both chords? Neither? A "floaty" feel about the resolution? That's the
tonality of a mode, it's hard to pick.
Now add just one chord to it. i - ii - V. Where does it resolve to now?
The i. Whilst the progression always resolved to the i (it has to), by
adding this extra V, the resolution is much, much stronger. This is the
feel of a major/minor key. The resolution is extremely strong when
compared to a mode.
2. Major/Minor Scales with Accidentals
Over a song in a major or minor key, you will always be playing a major
or minor scale. However you can also use accidentals, giving you access
to all 12 tones. You can derive scales from the modes and play them over
songs in major/minor keys, for example you can use a major 6th in a
minor key, and you'll have a scale which shares the same notes as
dorian. You're actually playing the minor scale with a major 6th, not a
mode.
3. Chord Scale Theory (CST)
This is also a method applying modal scales to major/minor scales. The
idea however is to consider each chord as an island, unrelated to the
next.
So say we have a progression in C major, an I - ii - V - C Dm G. Chord
scale theory basically divides modes into major and minor modes. The
major modes are those with a major 3rd. So they would be ionian, lydian
and mixolydian. The minor modes are those with a minor 3rd - aoelian,
phygian and dorian.
As the purpose of CST is to grant the player access to extra
accidentals, instead of simply playing the C major scale over the I -
ii- V progression, the player instead will look at the I, and play a
major mode over it, one that does not share exactly the same notes as
the C major scale. So C ionian is out for the I, instead they will play C
lydian or mixolydian over the I. Over the ii, for the same reason they
will not play D dorian, instead they will play D phrygian or D aoelian.
Over the V they will not play G mixolydian, they will play G ionian or G
lydian.
This grants access to extra accidentals. It's mainly used by jazz
musicians, where the pieces are extremely complex in terms of chord
progressions, compared to mainstream music.
Although they are deriving the scales from modes like approach number 2,
they are still playing the C major scale, that's where it resolves to.
These 3 methods are all acceptable approaches to modes, as long as each
is understood. You don't necessarily need to practice these in your
playing, but a general understanding of how each works is preferred,
especially why numbers 2 and 3 are merely visualising accidentals,
rather than actual modal playing.
And finally the most popular and least correct approach to modes is:
4. The dumbed down CST approach
You can see how people with very little patience would have created this
one. Somebody showed them that if you played over one chord in approach
number 1, it created a different sound. They then took a brief glance
at CST in number 3 and boom, they have number 4.
In this approach, it's very similar to CST in that each chord is treated
like an island. We'll use that I - ii - V progression again. Whilst in
number 3 above I explained why someone with the CST approach would not
prefer to use ionian over the I, dorian over the ii, and mixolydian over
the V, that's exactly what number 4 does.
So they play C ionian, D dorian and G mixolydian over our progression in
C major. The notes of C major over the key of C major. It's just the C
major scale.
Additionally users of this method will praise how they achieve all the
different sounds over these chords, and claim that each chord is a new
resolution and that through their soloing they have now shoved the
progression from C major into 3 separate modes. Good stuff.
However, in fact they are just playing the C major scale. Even worse is
that they aren't even employing accidentals, so there's no change in the
sound. They have convinced themselves somehow that the resulting sound
is very, very different to the C major scale, even though it is the C
major scale, and nothing more.
There are a lot of videos on youtube teaching this method. As soon as
the teacher says "i'm gonna teach you the modes in the key of C major" I
turn it off. These people will continuously show up in this forum too,
and profess that number 4 is the only way to play modes. They appear to
be the most closed minded.
So you can understand why we drill pretty much every new person who comes in here who claims to know modes. Most don't.
so... since we have had our disagreements in the past I feel it necessary to inform you on the true nature of modes, they are IDPLMAL Ionial/major, Dorian, Phrygian, Lydian, Myxolydian, Aeolian/minor, Locrian (the bad one) these correspond to the degree of the major scale, I ionian, II Dorian, III phrygian, IV Lydian, V myxolydian, VI aeolian, VII Locrian...... but you can harmonize with any that share the same notes so C major harmonizes with C major/G Myxolydian, or C myxolydian..... its all based on which notes in said scale correspond with said chords