Why doesn't this work backwards?

Tannin

We are in the key of G. Not really in G major or G minor, we are swapping back and forth the two so often that it can be hard to say which one we are in at any particular moment. It's not exactly a blues tune, but leaning that way.  The chord sequence I'm interested in is as follows:

C9: x3233x

Bbmaj7: x1023x

Am7: x0201x

Ab7: 4345xx

G9: 3233xx

Play it that way around and it is (to my ear) a very pleasing way to come back to the I from the IV. Play the exact same chords in the opposite order and it doesn't work at all.

I can guess part of the answer. The sequence starts on the IV and finishes on the tonic. In addition, the next-to-last chord is a bII7 - i.e., a tritone substitution for the V7. (So the last three chords are almost a 2-5-1.) I can see why the chord sequence wants to resolve to the root. Does that answer my question? Or is there more to it that I haven't figured out yet?

Bonus question: suppose you wanted to do something similar in style, but working up to the IV from the root? Right now I'm walking the bass up to do that, but what else could I do?

tabano

moving up I would swap that  Bmaj7 for a Bb7 flat 5, and very possible I would think of it as being in the Key of C, especially moving towards C9,
G9 would be the V, Ab7 would be altered heading to Am, B7flat 5 would be tritone substitution of E altered( V of the relative minor key of C, Am)
my first impression just based on the progression without a specific written melody,..

Tannin

I like it! Thanks Tabano.

Grangousier

If you harmonise a scale and move through it - so Cma7 /  Dm7 / Em7 / etc - then find the chord that fits between each of those chords (so if it's a semi-tone, like E-F you just stay where you are), you get:

Cmaj7 / C#m7 / Dm7 

That is to say, the in-between chord is the same as the one that comes next. On the way down, though, same things happens, so it's 

Dm7 / C#maj7 / Cmaj7

So your chord progression backwards would need to be G9 / Abm7 / Am7 - when there's chromatic movement like that, the transitional chord matches the chord it's moving to. 

I haven't picked up a guitar to check your chords, so may be so far off-beam that I'm in a different galaxy, but that's what the question suggests to me. 

(Pick a chord and a scale - say Cmaj7 in C major, keep it easy, why not - and move the notes up and down chromatically, but when there's a semitone play the first note twice until the other notes can catch up. You'll see what I mean.)

Basically too much coffee, sorry. 

tabano

Tannin said:

I like it! Thanks Tabano.

Glad you do!
cheers,

Tannin

In a nutshell, play the chromatic chord in the same flavour as the diatonic one I'm going to play next. Simple! Those are great tips, Grangousier. I'm having fun with them. Thank you.

carlos

Those last two voicings with the 4 lowest strings all sounding at the same time... ugh.
Anyway, this one isn't right

G9: 3233xx

The last note is a m3 so maybe 3232xx ?

Tannin

Quite right, it is of course a G(#9) or G7#2.

As regards using the 4 lower strings, well, we can see you are not an acoustic player at heart. Different thing if you have a bass player to keep out of the way of. Playing solo, the low strings are the main ones.