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Why do we say, "the Scale IS the Chord, and the Chord IS the
Scale"?
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As you know, you can build chords off each tone of (most) scales. For a time, theory was content to
define the triads
and seventh chords that can be built on the degrees of a given scale. But chords are way bigger nowadays...
"So what scales should I play over these chords?" Well, maybe that's really not the right
question, considering that in reality,
"the Scale IS the Chord, and the Chord IS the Scale". Here's why.
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Think about it: Chords are scales arranged by skipping every other note, or
'stacking thirds'. Scales are chords laid out sequentially.
And because those two things are true, it's easy to know what chord to play over a scale -
They are one and the same. The scale and its 'signature chord' are just a pool of notes that,
when they occur in a piece of music, provide our note choices for improvisation.
Every mode of the major scale yields a 7-note chord, so given the chord, you know the
scale to play.
But wait - A C major triad is NOT a scale. True enough.
But a C major scale IS a chord : Cma13, actually. (Including the 4th degree which is
usually dissonant and not played.) And the C major triad is a subset of the Cma13 chord.
So it could be said that the C major triad is a partial Cma13, and a part of a scale.
And it can be said that the C major scale is at least one scale that can be played
over a C major triad, because it contains the C major triad.
Typically when we think of the component chords of a scale, we think about the triads built on the
degrees of a scale, or the 'seventh' chords built on the degrees of a scale. The resulting chord types -
major, minor and diminished triads, or ma7, 7, mi7, half diminished chords, etc. - are small ambiguous
fragments of some scale that may occur at multiple places in that scale - And each fragment
can actually be part of many different parent scales.
Filling-in the Missing DNA.
Figuring out scales to play from triads and seventh chord scale fragments can seem a little like filling
in missing DNA sequences to get a complete genetic code.
To identify the parent scale for the chord of the moment, we look for the harmonic context,
the surrounding chords and choose a scale that contains those chords (dorian? phrygian?
aeolian? harmonic minor? melodic minor?) for improvising. In other words, we can never generally
assert "Over a minor triad always play a dorian scale." A minor triad has many parent scales,
so we can't generalize that way. We can't say "over a mi7 chord always play a dorian scale" either,
if the mi7 chord we refer to consists of only 4 notes, the 1, b3, 5, and b7. There's not enough information
there to identify a particular scale, because a mi7 chord occurs in many scales.
These triads and seventh chords are actually scale fragments, so we look at the chord's context,
and then select a scale for the chord in context.
The typically ambiguous way we name chords really doesn't communicate much
information about the parent scale without the context of the surrounding chords.
Lose the Ambiguity!
Our chord naming conventions often create unintentional ambiguity. As we saw above, a lone triad or seventh chord
doesn't tell much of the harmonic story. In a chord progression, the musician
resolves ambiguity by looking at the surrounding harmony and figuring out what modes are possible
within the harmonic context.
Ambiguous? Take for example, a mi7
chord: A Dmi7 chord built on the ii of a scale is not the same as a Dmi7 chord built
on the iii of another scale and on the vi of another! See the following examples - Traditionally
the seventh chords of the C major scale would be listed:
I - C ma7
ii - D mi7
iii - E mi7
IV - F ma7
V - G 7
vi - A mi7
vii - B half dim.
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Although it's not apparent from the chord names, the ii, iii, and vi will
all exhibit different extensions, as do the I and IV. For example,
the ii chord, extensions are the 2, 4, and 6. For the iii chord they are the b2, 4 and b6. For the vi
chord they are the 2, 4, and b6. But the basis for the mi7 chord, the 1, b3, 5, and b7, is common to all three!
Take a look at the chords of the C major scale, and notice that all mi7
chords are not created equal; nor are all ma7 chords:
I - C ma7 (has 2, 4, and 6)
ii - D mi7 (has 2, 4, and 6)
iii - E mi7 (has b2, 4 and b6)
IV - F ma7 (has 2, #4, and 6)
V - G 7 (has 2, 4, and 6)
vi - A mi7 (has 2, 4, and b6)
vii - B half dim. (has b2, 4, b6)
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So it's clear that the overloaded names "mi7" and "ma7" are ambiguous, as each is used to represent more than one chord.
But there is no ambiguity if we account for the extensions (2, 4, 6)
in the chord names somehow. That resolves the ambiguity. When we do so, we actually get a chord name identifing
the largest chord
possible on any given tone of a scale: That chord contains ALL the notes of that scale (1, 2, 3, 4, 5, 6, and 7). For example,
any chord built from C major or any of its modes will be comprised of CDEFGAB.
This is the basis of "Chord/Scale Theory". A unique chord is built on each degree of the scale
this way, as unique as the mode itself. D dorian consists of DEFGABC. E phrygian is EFGABCD. A minor
(aeolian) consists of ABCDEFG. Etc. Using the C major scale as an example, the
chords of the scale are really
I - CDEFGAB (ionian)
ii - DEFGABC (dorian)
iii - EFGABCD (phrygian)
IV - FGABCDE (lydian)
V - GABCDEF (mixolydian)
vi - ABCDEFG (aeolian)
vii - BCDEFGA (locrian)
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(The 4th of any chord will generally be an 'avoid' note, a dissonant note, in both chord and scale.)
There is a chord for each mode. Each mode is a chord. This eliminates any ambiguity. The chord is actually the
entire scale. Even though when playing chords sometimes we simply omit the upper voices,
they are always still 'virtually' there. So, for this reason, we say the
Scale IS the Chord, and the Chord IS the Scale!
Chords are bigger nowadays, but the names are still small: The issue
of ambiguous names...
It's clear that all mi7 chords are not created equal, nor are all ma7 chords created equal. So how do we name these things so
we can tell which ma7 or mi7 we're talking about?
To get around this ambiguity in the ma7 and mi7 chord names, some theorists have proposed ensuring each mode of a given scale
a unique name to identify to the improviser exactly what degree of the scale is intended. Where our typical
name will suffice it is used, and any extensions or alterations are implied. One such naming system:
CDEFGAB = C ma7
DEFGABC = D mi7
EFGABCD = E sus(b9)
FGABCDE = F ma7(#4)
GABCDEF = G 7
ABCDEFG = A mi7(b6)
BCDEFGA = B half dim.
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(ionian)
(dorian)
(phrygian)
(lydian)
(mixolydian)
(aeolian)
(locrian)
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In fact, the name of the chord becomes synonymous with the scale - The dorian chord, the phrygian chord,
etc., or the mi7 scale or the sus(b9) scale. The idea is to eliminate the ambiguity and clearly identify
the intended degree/mode of the scale. Notice that the names ma7, mi7, 7 and half dim. are still used, but this time
only where the 2, 4, and 6 are not flatted or sharped. Where the extensions are modified, the name reflects the modification.
There's no ambiguity. The extensions are implied, not omitted. We have new unique and
wholly descriptive names for the 'duplicate' names.
(The above "chord/scale" process is applicable to all modes of all scales, harmonic minor, melodic minor, etc.)
In summary...
Ultimately you have to know what the function of the chord is to determine what to play over it.
Is this minor chord the ii, the iii, the vi? Is this major chord the I, IV, or V? One way to
communicate the specific function of the chord is by using the chord/scale name.
Whether the names are ambiguous or not, always try not to think of "What scale goes with this chord?"
Think, instead, "the Scale IS the Chord, and the Chord IS the Scale"!
Copyright ©2002-2008 by Groveland Software Labs, Inc. All rights
reserved.
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