Originally Posted by: FlyingJbird
Okay, so it sounds like this method would require looking at the song and analyzing it before hand.
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Absolutely! :) Of course, the more you do this sort of thing, the quicker you can assess the possiblities and lessen the time between data gathering & application.

Originally Posted by: FlyingJbird
Okay, so let's look at an example. This is the sheet music I have for Manha De Carnaval (Black Orpheus)
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The song is in A minor, good start. The question is becomes about dealing with those "exceptionally colorful chords". You must identify them and how they function. Are they functional or ornamental? Will your approach to them be functional or ornamental?

My video you mention is about a common classical & jazz technique. The idea is to prepare for the arriving chord. You can do this to any degree you want. If you can play fast enough, you could do this for every chord! Or you can do it 2 or 4 measures at a time. Or you can do it to match phrases. You can do it only when an actual modulation occurs. The choices you make in this regard is (or is what becomes) your own style. This is why Tatum sounds like Tatum, Bird sounds like Bird, Coltrane sounds like Coltrane, Martino sounds like Martino. etc. :)

So when you ask:
[QUOTE=FlyingJbird]
Obviously, the A minor/harmonic minor scale works fantastically for the first set of chords, which is your basic 1-2-5 jazz progression. What scale might I pick to modulate over to the next chord set, which is Amin7-Dmin7-Gdom7?

First, A harmonic minor IS a modulation. It is an altered scale! It's altered from the A minor natural, which is the relative minor of C major. And the key of C major is where this chord progression comes from in the first place:

A min (vi) - G7 (V7) - C (I)

Consider the very next chords:

C# dim7 (vii of ii) - D min7 (ii) - G7 (V7) - C6 (I)

Quite obviously we are in C major here. Ergo, D minor doesn't work as well as D dorian (being the 2nd mode of C major).

Notice that anytime the song uses an E chord with a major 3rd (G#) this implies the modulation to A harmonic minor. And when the song uses a G7 this implies A natural minor or C major.
[QUOTE=FlyingJbird]
Dmin scale is the same as an A Phrygian scale, I think. So would I be right in using an A Phrygian scale right before the chord change?

D minor scale contains these notes (D-E-F-G-A-Bb-C-D). Relative minor of F major; 3rd mode is indeed A phrygian. But it doesn't fit the song's melody or chord progression (there is no B-flat note; the song doesn't emphasize D minor or F major as a home key or strong key center).

So, you can of course play it, it will add a certain amount of dissonance. Just be aware of that fact.

Notice there is a modulation to D minor later on in the B section m.21. This is a very important "pivoting point" in the song in helping to change focus of tone center. Suddenly E7b9 (functioning as V7 of A) becomes Emin7b5 (functioning as ii of D minor; A7b9 as V of D minor).

However, if you wanted to get really bebopish, you could imply D minor scale right before any and all D minor chords regardless of the chord or key that is happening right before the D minor chord.

For example, in m.5 while the A min chord is happening, you could play notes from D minor scale that imply Emin7b5 (D minor) and then A7b9 (V of D minor). This sort of clashing dissonance with the A minor chord being played at the time is typical of some jazz. And some argue that it is actually an integrated idea or approach because it suggests (or "points to") the eventual arrival of the D minor key later on (which actually does happen). And some jazz guys would then find something else dissonant to play when the D minor modulation actually does arrive! Whew!

Make sense?!