[HANASHIR:1570] Re: tritone substitution

[eblank <eblank...>]

Rick:  Is the ii sort of a "substitute" for the IV?  Emily

----------
> From: Rglauber (at) aol(dot)com
> To: hanashir (at) shamash(dot)org
> Subject: [HANASHIR:1568] Re: tritone substitution
> Date: Monday, October 26, 1998 9:58 AM
> 
> OK Emily, since you asked.....
> 
> The tritone substitution is one of the basic ways that jazz musicians
(and
> others) spice up a chord progression.  It has to do with the tritone,
> otherwise known as the interval of a flatted fifth.  The reason it's
called
> the tritone is because it consists of three whole steps (tones).   If you
> start on the note C, to find the tritone, you go up one whole step to D,
one
> whole step to E, and a third whole step to F#.  So the interval between C
and
> F# is a tritone (or flatted fifth).
> 
> Now there's something very special about that particular interval.  There
is a
> tension inherent in the tritone, and it's a tension that wants to
"resolve" to
> a more harmonious state.  In fact this tension--resolution is at the
heart of
> our western music, classical, rock and roll, jazz, country, blues, it all
uses
> the same basic building blocks, the major one of which involves the
> tritone....
> 
> Let's say we're playing a song in the key of G.  Nine times out of ten,
the
> end of the song will go something like G D7 G.  That D7 chord resolves
> extremely strongly to the G chord to give us a sense of completion and
rest.
> Everyone can sense it instinctively, everyone can hear it easily.  But if
we
> want to know WHY this is so, the answer is the tritone.  The D7 chord
contains
> the notes D  F#  A  C  (I  III  V  b7).  The key notes here are F# and C,
in
> that they create the "tension" that just needs to be resolved, in this
case by
> going from the D7 chord to the G chord.  (Yes a straight D chord will
also
> resolve comfortably to a G chord, but it doesn't have the compelling
force
> behind it that a D7 chord has)
> 
> Here's where I'll lose some of you  (assuming anyone is still reading,
that
> is), but the intent of this is to explain the "tritone substitution".  
F# and
> C exist in the D7 chord as the third and flat seventh of the chord.  They
also
> exist (in reverse order) as the third and flat seventh of the Ab7 chord. 
(Ab
> C  Eb  Gb(F#)).  It's still a tritone, and it still wants to resolve,
still
> needs to resolve.  
> 
> The "tritone substitution" allows you to substitute an Ab7 chord for a D7
> chord.  So that G  D7  G could be altered by playing G  Ab7  G.  How do
you
> know that the "substitute chord is Ab7?  It's a tritone away from our
original
> chord of D7.  Here are some basic tritone substitutions, and if you
understand
> these, I'm sure that you can complete the list.
> C7    F#7
> D7    Ab7
> E7   Bb7
> F7   B7
> G7  Db7 
> 
> Final thought.  These substitutions don't maks a lot of musical sense on
their
> own.  In other words you wouldn't play "Frere Jacques" and employ the
tritone
> substitution.  This type of harmony works best if you are already in the
> process of jazzing up your music.  Also, this substitution is only a
starting
> point, it's not the end in itself.  There are many many ways of
substituting
> for a D7 chord, and the correct choice depends entirely on the musical
> context.  The real use of tritone substitution occurs when one is aware
of the
> basic ii  V  I  way of jazzing up popular music.  If anyone is interested
in
> that idea, I'm happy to share.  
> 
> If anyone is upset by the length or subject matter of these "theory
sessions",
> I'd like to know that as well...
> 
> Rich Glauber
> 
> 
>