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Musical Theory Abound!!!
 #12174  by mttourpro
 Mon Jan 29, 2007 3:12 pm
I remember hearing people (jazzers) talk about chord substitutions. I recall hearing about using "tritone substitutions" which I can only assume means something like playing the same type of chord (Min, Maj, Dom, etc) a tritone away from the chord you're, for example, playing an F# minor where you'd normally have a C Minor. It generally sounds bad/odd to do this but I assume I'm missing something or other. Maybe they're just used as a "passing chord/tone" on the way to another chord (like on the and of four, before the change??), or, maybe there's a more accurate and better sounding way to utilize such weirdness.....anyone know anything about this idea??

 #12177  by Rev_Roach
 Mon Jan 29, 2007 3:55 pm
if i remember correctly you pretty much got the idea. the thing is i think it only works for dominant chords. sevenths and higher ones like 9 and 13.

the reason for this is the following: any dominant chord has a "defining" tritone that gives the chord it's dissonance. the tritone is between the 3rd and 7th. (ex. G7 tritone is B to F). Notice that a tritone is the same in either directions since it is 6 of the octave's 12 half-steps. B to F is just as far as F to B.

So if you shift your domiant chord by a tritone, think G7 to C#7, it has the same defining tritone.

G7 - G B D F
C#7- C# E# G# B

(E# is equivalent to F.)

As for when/where to use tritone substitutions, you're on your own there. Tell me if you learn something good...

 #12178  by mttourpro
 Mon Jan 29, 2007 4:22 pm
Very cool. Thanks RR. I thought it might only be for one type of chord....I'm gonna mess around with it and try to apply in various ways. Might be cool on some of the Blues for Allah and Wake of the Flood stuff.
 #12189  by lyghtningod
 Mon Jan 29, 2007 9:57 pm
Rev Roaches points are spot on. Here's a few more ideas.

Take a basic progression of I vi ii V, in G it would be G Em Am D
by flat 5 sub we could rewrite that as
G maj7 Bb7 Am11 Ab7b5.

3-x-4-4-3-x is the G
6-x-6-7-6-x is the Bb7
5-x-5-5-3-x is the Am11
4-x-4-5-3-x is the Ab7b5

Sorry that's not more clearly written. My first time

Try playing through that and you'll hear some really nice voice leading

Or this one

Gmaj7 as above
Bb7 as above
x-6-8-7-8-6 Ebmaj7
4-x-5-5-4-x Abmaj7

According to the Mel Bay Jazz Method, where I got those examples, there are a number of ways to do substitutions:


Each has different sound,
Good luck.

 #12202  by mttourpro
 Tue Jan 30, 2007 12:55 pm
Thanks for the info and ideas....I appreciate it. I'll have to try those out and experimenmt a bit...MT