"You wrote: 1. The phrase "natural minor" is generally reserved for Aeolian mode. Dorian mode is not part of the conventional minor key scale set.
As I wrote in the introduction (paraphrased), "possibly the only surprise here might be that there are four minor scales, as opposed to the three that all other theory books list (Aeolian, Melodic, Harmonic)"."
Sorry I missed that sentence.
But then, if you are going to include Dorian, why not Phrygian? (I know it's rarer, but still a minor mode.)
Still, as long as you are pointing out the differences between your approach and conventional theory books, that's fine.
"Indeed in common use, most Dorian tunes are commonly referred to as being "minor" (ex: Â¿Oye Como Va?)."
Sure. I think, strictly speaking one wouldn't say Oye Como Va was in the "A minor key" - but I accept the broad sense of "in A minor" can include Dorian mode.
I personally think it's useful to make the conventional distinctions - because a Dorian mode tune is usually quite different from a minor key tune. And Aeolian mode is different again (tho more subtly).
But I've got no real quarrel with your broader, inclusive approach. These are analytical issues (understanding existing music), rather than what's useful for making our own music. For the latter, as broad an approach as possible is best.
"You also wrote: 2. This is a very confusing statement: "In the case of the Dorian and Aeolian modes, the dominant is the chord built off the 4th and b7th respectively".
The dominant chord in a minor key is the V chord. Built on the 5th step. (E or E7 in A minor.) I suspect you know this, but I think you need to explain what you mean in that quote. (I think I know, but I can see it confusing some people, and I'm not sure of the relevance in that part of the lesson.)
Even if referring to classical modal theory (as distinct from key theory), the dominant note is still the 5th of the scale.
The chord E major or E7 does not reside within the pure Aeolian mode due to its G# which is outside the tones in the Aeolian mode.
Anytime you use a major or dominant chord built off the 5th degree in an otherwise Aeolian progression, you are using borrowed parallel major harmony to effect the cadence.
Yes, that's one way of looking at it. Minor key harmony can even be explained historically in that way.
But it remains the case that a dominant 7th chord on V is normal in minor keys - not abnormal in any way.
Of course, it's different from Aeolian mode in that respect.
That's how we define the difference between "Aeolian mode" and "minor key".
IOW, the concept of "minor key" (in pop and rock as well as in classical and jazz) includes the major V chord as standard. It's traditional, but still widely used.
A minor v would be more unusual, and would suggest (IMO) a deliberate choice of Aeolian mode (or possibly Dorian).
"In pure Aeolian harmony, the dominant is the chord built off the bVII of the Aeolian mode.
This is not an opinion, it is fact."
Well, it's a slightly misleading use of the term "dominant". You mean a "dominant 7th-type chord" is built off that step.
You don't mean "dominant" in the conventional (theoretical) sense, which refers - almost always - to the 5th step of a scale or mode. It's a note before it's a chord.
In a functional sense, the bVII chord of Aeolian (or the IV of Dorian) is only a "dominant" chord in the relative major key.
I think this is important, because it's about consistent definition of terms, to avoid confusion.
The bVII of Aeolian is NOT the dominant degree. (That's the 5th.)
BUT a "dominant 7th type chord" (the true dominant chord of the relative major) is built off that step. In the context of Aeolian, it's the "subtonic" chord, not the dominant chord (of Aeolian).
As long as we're on the subject of modal dominants, remember that the dominant of the Phrygian is the bII, and that the dominant of the Mixolydian is the bVII.
This is making less sense, unfortunately.
If you mean the step on which a "dom7th-type" chord is built, that's III for phrygian and I for mixolydian.
The "dominant degree" of each scale is still the 5th, whatever type of chord gets built there. (Historically, I think the dominant of phrygian was actually the 6th for a time, but that's modal history.)
Please don't take my word for this (definition of "dominant"). Check some sources:
Only the Ionian has as its dominant the 5th degree.
If you have any dispute with this, all you have to do is play the tonic of any of these non-Ionian modes, and then play the chord built off its 5th degree and you will immediately hear what I'm talking about.
You're just using the word "dominant" incorrectly. What you're saying is quite right otherwise, of course.
When we want to create a major key-style perfect cadence (in Aeolian mode), we construct a dominant 7th-type chord on the 5th degree .
We alter the usual "dominant" chord (which is minor), to make it the same as an Ionian dominant chord (which is major, with a minor 7th).
The problem here is that word "dominant" has come to refer to that specific chord type, as well as to its function. The mistake is to refer to a chord as "dominant" when it doesn't have that function (even tho it might have that structure).
It's misleading (IMO) to call the bVII chord in Aeolian "dominant" - without a proper explanation of the term.
If you can find an authoritative online source which supports your argument and counters mine, I'll take it all back! :-)
"You also wrote: 3. The "Circular Minor Chord Sequences Table" is not very clear. Why the two columns? How do they relate horizontally? I'm not quite sure which chords you're referring to.
The two columns exist because a neat circular movement is not possible. The only horizontal relation is that the bIII and the VI are tritone substitutions for one another as are the bVI and the II."
Hold on. In key of A minor, C (bIII) and F#dim (VI) are not tritone subs of each other. Nor are F (bVI) and Bm7b5 (II).
The roots are a tritone apart, yes. But tritone subs need to be the same chord type, and also need to be dom7 chords.
The only real tritone sub in a minor key is the bII (Bb7 in A minor) which subs for E7.
C and F#dim are quite different sounds (as are F and Bm7b5), so function differently. Therefore they can't sub for one another.
It can still be argued that a "neat" circular sequence exists. One of the 5ths (or 4ths) is not perfect, but it still works. In key of A minor, Fmaj7 can move logically to Bm7b5 - and it works as a chord change, not as a pair of equivalent subs.
"RE: bIII vs III (etc)
In order to have zero ambiguity, I have chosen to call a chord built of the scale degree that is a minor 3rd above the root as a "bIII", etc."
Given that you are referring everything to major "template", for a broad overall view, I accept this. (No big deal, different systems work in different contexts.)
"RE: Dominants built of the natVII degree
If one is using borrowed parallel major harmony to create a dominant function, then it is perfectly kosher to use the chord built off the natVII degree even in what is otherwise an Aeolian or Dorian tune.
addendum: The V and natVII are not only built off the Harmonic minor scale, they also occur when using the Ascending Melodic minor scale."
Not quite. If the V and vii chords are extended (at least as far as standard jazz practice goes) you get a 7b9 on V, and a dim7 on vii. These are Harmonic minor chords, not Melodic minor.
You may occasionally get a melodic minor V (a dom9), but I don't think I've ever seen a melodic minor vii chord (m7b5).
Of course, I'm speaking of "common practice", not potential usages. If your angle is on the latter, that's fine.
"You also wrote: 5. "Autumn Leaves" is (in my experience)) normally analysed as a ii-V-I-IV in the relative major to begin with. Then ii-V-i in the minor.
If you prefer to think of that progression as bi-tonal, that is certainly on way to look at.
Wel, it's not just me. It's every jazz musician and tutor I've ever encountered. Of course, it can be seen as entirely minor key. I would say THAT is the "alternative" way of looking at it. ;-)
"There are a great number of minor tunes that use extremely similar progressions (as you are certainly well aware), and everyone I've ever played with has called that tune as a minor starting on the IV."
I do see the double action of the initial chord (iv in minor as well as ii in relative major). But I also see the final minor as a double-action vi in the relative major.