Need help analyzing what I transcribed.

[AMp'D.2play]

I've been transcribing songs as part of my learning process.

A song I'm working on pretty much uses only 2 chords through the main sections. Assuming I have the notes right (they sound right to my ears), the arpeggios are bars of A-C-D-F followed by C-Eb-F-Ab. From my limited theory experience, the first chord could be the 2nd inversion of a D minor 7th; the 2nd chord could be the 2nd inversion of an F minor 7th. (The b3 of these chords ... F/Ab ... are only used in every 2nd bar.) I've found they could also be Major 6ths of F/Ab, but I've only been exposed to the primary chords so far.

The middle of the song then moves to riffs that begin on the D, so I'm *assuming* the key is D minor. The majority of the notes in these riffs fall into a D Locrian.

My questions are, a Dm7 to Fm7 would be a i-iii progression. Is there such a thing? If that's the case, I wasn't aware a progression could use a i that's not a major (I)?

[mambo4]

edit: F7 should have been Fm7

Dm7 and Fm7 are not strictly in the same key: one has an A and one has a Ab.
so trying to anylize them in terms of diatonic harmony (major scale and its modes) may be troublesome.
lots of minor/diminished sounding music will ignore straight up major scale diatonic 'rules'.
Just having root notes follow a minor or diminished pattern and making the chords whatever sounds appropriate.

D locrian implies a the key Eb...which technically would imply that Dm7-Fm7 is a vii-ii,
with the vii chord simplified from a Dm7b5 (D F Ab C) to a Dm7

any progression in a minor key will use a i thats not major, but then you're dealing with the harmonic minor scale, not a diatonic one.

BUT there's no reason you can't call it iii-i if you want... theory is not "rules", just labels.

[FretlessMainly]

I think there's some confusing info in Mambo4's response (no offense).

1. If you are in a minor key, you are not necessairly dealing with a harmonic minor. One could be in d natural minor and use a d minor scale (d aeolian or F Major). Thus you have the possibility of a d nat minor scale with chords that are diatonic to d nat minor (dmin7, emin7(5), FMAJ7, gmin7, amin7, BbMAJ7 and C7).

If the chord A7 is there, you have the C# and thus the d harmonic minor.

2. D locrian does indeed indicate EbMAJ, but without the Dmin7(b5), you lose that EbMAJ character. But a VII-II in Eb (i.e., Dmin7(b5)-Fmin7) wouldn't be outside the realm of making sense (except we don't have the Ab). As Mambo said, we could have a simplified version with Dmin7-fmin7, but that wouldn't all be in EbMAJ.

3. Dmin7 and F7 can indeed be in the same key: the key of BbMAJ, if Dmin7 is functioning as the III chord and F7 as the V chord. But, I doub't you have that in your situation, just because a III-V is not a common vamp style change.

It is possible that you have Dmin7 to F7, where the Ab is there as a #9 rather than as a b3. The #9 is used over dominant chords in blues all the time. So, check to see if the F chord is really an F7 (play a natural and decide if it fits) and the Ab is just a "blue note."

Once you've determined whether you have an F7(#9) or an fmin7, you can hone in on just what the chord labels are. As Mambo says, theory isn't really rules, it's more like labels for the sake of communication and interpretation.

[mambo4]

I didn't even think of 7#9 chords...good point.

And yes, minor progressions can be based on variety of minor scales.
Natural minor (which is diatonic) is as common or more so as the harmonic minor.
I din't mean to imply that you "have to" use harmonic minor -just that a minor i can throw a wrench into analysis at times

Context, of course ,determines all.
Different styles will break /ignore different theoretical "rules"
Is this a Death Metal tune?
A bluesy tune?
a Modal Jazzy tune?

Each one might imply a different approach to analysis.

Very often the chord motion can be understood from the root in terms of roman numeral chords ( its a I-IV-V, thats a ii-V-I ect)
while the actual chord qualities (major, minor, Dom7 ) may ignore the diatonic "rules"
-Blues being the obvious example. A7-D7-E7 technically changes keys with each chord, but it's still generally consider "Blues in A"

[AMp'D.2play]

Originally Posted by mambo4

Context, of course ,determines all.
Different styles will break /ignore different theoretical "rules"
Is this a Death Metal tune?
A bluesy tune?
a Modal Jazzy tune?

Porcupine Tree, song is Neural Rust. I'd never heard of them prior to October. Now I can't stop listening to them. I guess they fall into the Prog Rock genre, which would be fitting since that's what I enjoyed in the 70's & 80's.

[FretlessMainly]

Porcupine Tree rocks it out; heavy prog-metal prog, but more heavy than metal (there are something like 15 genres of prog alone!). I saw them with Fripp and Belew (projeKct six) opening at the Berklee Performance Center a couple of years ago.

Anyway, I just found the tune online and I would say what you have is a case of a lick in d natural minor followed by a parallel lick in f natural minor. The music doesn't really have a 6th in it, so I can't be positive they aren't thinking lydian for each, but to me, the b6th fit melodically, so I'd say you have two keys and two chords: dmin (chord = dmin7) followed by fmin (fmin7) then back to dmin.