+1 to TJ UKE. Any
scale (given by the key signature), can begin and end on any note, which acts as the root of that
mode.
The
key of C major has no sharps and no flats...
Code:
... begin and this scale on the note of C
& the mode of C [I]Ionian[/I] is: CDEFGAB[C']
with scale intervals: TTSTTTS[T']
Begin & end the same scale on the note of D
& the mode of D [I]Dorian[/I] is: DEFGABC[D'] (no sharps, no flats)
with scale intervals: TSTTTST[T']
Begin & end the same scale on the note of E
& the mode of E [I]Phrygian[/I] is: EFGABCD[E'] (no sharps, no flats)
with scale intervals: STTTSTT[T']
Begin & end the same scale on the note of F
& the mode of F [I]Lydian[/I] is: FGABCDE[F'] (no sharps, no flats)
with scale intervals: TTTSTTS[T']
Begin & end the same scale on the note of G
& the mode of G [I]Mixolydian[/I] is: GABCDEF[G'] (no sharps, no flats)
with scale intervals: TTSTTST[T']
Begin & end the same scale on the note of A
& the mode of A [I]Aeolian[/I] is: ABCDEFG[A'] (no sharps, no flats)
with scale intervals: TSTTSTT[T']
Begin & end the same scale on the note of B
& the mode of B [I]Locrian[/I] is: BCDEFGA[B'] (no sharps, no flats)
with scale intervals: STTSTTT[T']
The mode of C Ionian, you'll notice, is simply the key of C major. You may also notice that the mode of A Aeolian is similarly, just the key of A (natural) minor.
How to apply this? Let's say you're noodling over a 12-bar blues in C. In each bar, you're beginning and ending each phrase on the
root note of the relevant chord. These then are the modes you'll be employing as you do so:
Code:
|C / / / | / / / / | / / / / |C7 / / / |F / / / | / / / / |
Ionian............................... Lydian............
|C / / / | / / / / |G7 / / / | / / / / |C / / / | / / / / |
Ionian.......... Mixolydian........ Ionian............
Let's now try a 12-bar blues in Am (natural minor). Again, in each bar, you're beginning and ending each phrase on the root note of the relevant chord. These then are the modes you'll now be employing as you do so:
Code:
|Am / / / | / / / / | / / / / |Am7 / / / |Dm / / / | / / / / |
Aeolian................................ Dorian.............
|Am / / / | / / / / |Em7*/ / / | / / / / |Am / / / | / / / / |
Aeolian............ Phrygian............ Aeolian............
*[SIZE=1]Normally you'd use the harmonic minor scale, and so play an E7 (major) here, but this is a theoretical example :) [/SIZE]
You can see why the Ionian, Lydian and Mixolydian modes are classified as the
major modes (they all fit over major chords), while the Aeolian and Dorian and Phrygian are classified as the
minor modes (they all fit over minor chords).
Rock & pop musicians began experimenting with modes in during the 60s & 70s, in an attempt to get away from the conventions (as they saw them) of Tin Pan Alley. One notable example of a song that uses the Mixolydian mode is 'Heroes' by David Bowie. The stated key signature in this song is that of D major, but the chords employed belong to D Mixolydian mode in the key of G.
Allow me to explain
As you know doubt know: in their simplest form, chords are groups of 3 notes made up from every other note in a scale. So if we graph out the relation of the scale of the key of D major (Ionian mode), to the chords that derive from each note in the key of D (
n.b., that D can act as the root of the Ionian mode, TTSTTTS[T'],
only in the key of D), we get the chords of D, Em, F#m, G, A, Bm, C#dim (and D again; see below)
Code:
D Ionian
(scale/chords)
D E F#G A B C#D E F#G A
I D D F# A
ii Em e g b
iii F#m f# a c#
IV G G B D
V A A C# E
vi Bm b d f#
vii' C#dim c# e g
I D D F# A
Now, if we do the same thing for D Mixolydian, which starts and ends on the note of D in the key of G (
n.b., again, D can form the root of the Mixolydian mode, TTSTTST[T'],
only in the key of G), the chords that result are D, Em, Fdim, G, Am, Bm, C (and D again). The really big difference you'll notice is that the V chord (A in this case) is major in D Ionian, in the key of D; whereas in D Mixolydian, in the key of G, it's minor (see below).
Code:
D Mixolydian
(scale/chords)
D E F#G A BC D E F#G A
I D D F# A
ii Em e g b
iii' F#dim f# a c
IV G G B D
v Am a c e
vi Bm b d f#
VII C C E G
I D D F# A
Now let's look at the chords used in 'Heroes', nominally in the key of D major.
Code:
D G
I wish I could swim
D G
Like the dolphins, like dolphins can swim
C D
Though nothing will keep us together
Am Em D
We can beat them for ever and ever
Am Em D
Oh we can be Heroes just for one day
Yes, D, G, C, Em,
Am. The key signature (two sharps) says 'D', but the chords actually used in the song all belong to the key of G, not to the key of D (
n.b., there's no C [natural] in the key of D). Nominally the song's in the key of D (Ionian): in actuality it's in D Mixolydian.
I hope you're taking notes. I'll be asking questions later