Scales, Modes and Chords

[MrM]

Hi JumpingJackFlash, Cool topic.

I understand most of the theory, I have no problem understanding it. But I do have trouble using it.

For instance, it is perfectly clear to my that harmonizing a major scale (in C for example) results in:
I II III IV V VI VII = C Dm Em F G Am Bdim
Because the notes used are c d e f g a b (in that order!)

And harmonizing the minor scale (in A for example) results in:
I II III IV V VI VII = A Bdim C Dm Em F G
Because the notes used are a b c d e f g (in that order!)

Well, the above part is clear to me.
But what about modes?

Say we have a Dorian mode, and we use the scale of C.
C Dorian uses the notes of the Bb major scale: bb c d eb f g a

How do I harmonize this C Dorian scale?
Which note is the tonic, c I suppose?

So the I chord would be c eb g = Cm?

[jcivil]

Some parts may be a touch misleading. For example, you talk about the suspended chord as if it were a functional harmonic unit, but it's really a major chord WITH a suspension (a functional nonharmonic unit) which resolves.

Yeah, I was debating whether or not to put in the Suspend 4th or not. I decided to go with it because it's used a lot in popular music (where it often doesn't resolve properly, and is seldom prepared). You're right that it's not a harmonic unit in the same way as a diminished seventh is...

it's not as strong a one possibly, but a sus4 has places viz a goal or implied one that it wants to go, by its own structure in a context, and can be said to be a functioning harmonic unit I think.

EG: its use by Debussy for one did open the vertical thing to sonority as opposed to function in the old world sort of sense

[jcivil]

Hi JumpingJackFlash, Cool topic.

I understand most of the theory, I have no problem understanding it. But I do have trouble using it.

For instance, it is perfectly clear to my that harmonizing a major scale (in C for example) results in:
I II III IV V VI VII = C Dm Em F G Am Bdim
Because the notes used are c d e f g a b (in that order!)

And harmonizing the minor scale (in A for example) results in:
I II III IV V VI VII = A Bdim C Dm Em F G
Because the notes used are a b c d e f g (in that order!)

Well, the above part is clear to me.
But what about modes?

Say we have a Dorian mode, and we use the scale of C.
C Dorian uses the notes of the Bb major scale: bb c d eb f g a

How do I harmonize this C Dorian scale?
Which note is the tonic, c I suppose?

So the I chord would be c eb g = Cm?

(just to clarify your terms, 'scale of C' means to many of us the white keys, and D as a tonic gives you a dorian mode there)

"C dorian" (c as tonic) being key of Bb, two flats: Bb and Eb. "i" chord is C min 7, if you want to extend to four notes; the 9th, a major ninth: D, extend to 11th, perfect 11th: f

the characteristic sound of dorian, as opposed to 'minor' modes is the natural sixth, a in 'c dorian' and in a line it tends to indicate the 'IV' chord, in c dorian, f a c] and its quality of proximity to the ('flat') 7, Bb per a tonic C. in some jazz you get a temporary sort of mixolydian on IV (F), here F G A Bb C D Eb

[jcivil]

also, in harmonizing modal lines, one must take care with chords that like to function diatonically; prime example, D dorian (c major scale), the IV7 (g b d f) wants to go to VII, which sounds like (V7 >) I now, IE: destroys the mode.