GJ chord substitutions?

sockeye · March 2006

Does anyone have any good tips on chord substitutions in this idiom?

Advance warning: I know very little about jazz theory so some of what I say below may be incorrect.

I noticed while working on "Blues in Minuer" in Gm that when I go to the Cm6 (IVm6) that chord has a tritone in the m3-6 note pair -- the same interval shows up in the VIIm6, in other words F#m6 (2x12xx). So instead of 2 bars of Cm6 it sounds quite nice if I play 6 beats of Cm6 and then 2 of F#m6 and then back to Gm6.

Would that be a typical GJ sub?

Similarly, when I go to the V7 chord (D7) there's a tritone interval between F# and C. The same interval is in a G#7 but that doesn't sound right resolving to the tonic minor 3rd. The tritone is also in an Ebm6 (x3434x). This sub sounds quite nice, again for the last 2 beats before resolving back to the tonic.

Again, is that something that seems like a reasonable sub for this idiom?

Any tips on books or websites to help me understand which subs I might use where would be appreciated...

Jack · March 2006

I think a lot of what you can 'get away' with depends on the soloist-I know I've come up with things that sound great in isolation (practicing alone at home), but clash like hell once a lead voice is added. Often it's because of things similar to the examples you mention above: if you look again at the notes, you can still think of them as Cm (ex1) and D7 (ex2), but with altered chord tones (b5 in the Cm, #5 and b9 in the D7). Depending on what kind of sound you're after, things could get confusing.

That said-if the band likes it, I say go for it! These days I don't actually use true substitutions all that much, but instead use different voicings of the same chord. Simple example for Blues Mineur (Gm 6 beats, Gm 2 beats, into Cm...):

--x--------x------8---
--5--------8------8---
--3--------7------8---
--5--------8------7---
--5--------7------x---
--3--------x------8---

hope that helps...

Best,
Jack.