Chromatic Theory ?

[tocoadog]

So I'm writing more and transcribing even more. (Don't those go hand in hand...). Anyway, diatonic theory is no problem. For example, if I'm transcribing something in the key of C and the root note at the beginning of a measure is A, I'm going to assume the chord is Am(7). Okay, no problem there. What gets me is when the a chord goes chromatic, then I'll get lost.

My question is why do some chords out of a given key sound good together, while others don't? I understand parallel chords, substituting 5th for roots, like A7 for D7 in the key of G. I understand substituting chords with similar notes.

For example, why does Amajor sounds ok with Cmajor, but Cmaj doesn't sound too hot with Emajor when both A and E are outside of the Key of C?

Any theory would be greatly appreciated. tocoadog

[DocBop]

I think you need to keep digging into the theory. I assume you are talking about bass lines not solos. The first note of a measure isn't necessarily the root of a chord especially the more sophisticated the music. It could be an inversion of the chord or even an chord extension. Look at all the notes in the measure to and look for more chord tones, or try to recognize the scale being played.

Your second question about sub's I'm not sure what you are saying. "substitution 5th for roots" are you talking about tritone substitutions? With tritone sub's you can replace a Dominant chord with another dominant a b5 above it. This is because the tritone in both chords are the same two notes. So it wouldn't be A7 for D7 in G, it would be Ab7. It all has to do with voice leading and the notes resolving when it moves to the G.

To understand chords, where it came from isn't as important as where is it going. To me C to A isn't that common. C to Amin is and C to A7 would a Bluesy sound and next chord is probably a D.

I would say read more on the harmonized Major scale. Imaj7, IImi7, IIImi7, IVmaj7, V7, VImi7, VIIdim. Then the common chord subs Imaj7 you can use IIImi7 and VImi7. IImi7 you can use IVmaj7. Last V7 you can use VIIdim.

Then read up on strong root movements of chords and using Circle of 5ths to learn strong chord resolutions. You've started, just more to go. Modal interchange will explain some subs. Quick explaination is to use chords from the harmonized minor scale or same root. So song in C Major seeing a Ebma7 chord. That is modal interchange using the bIII chord of C natural minor. Then there's all the Jazz stuff with preceeding chord's with their V or II-V. And there more so you've scratched the surface still more to learn over time.