Last but not least, the Locrian mode is historically not a "true" church mode like Dorian, Phrygian, Lydian and Mixolydian and possibly evolved into being by theorists to fill the gap in their reshaping of the modal musical system into the more modern equal tempered system. With the Ionian and it's relative minor, the Aeolian mode being banned by the church for centuries, with the gradual emergence of equal temper during these times, only six modes where available. Well, there are seven pitches in the major scale / Ionian mode and thus the Locrian became the seventh mode.
So why is this mode important? Not generally used as a tonal center as with the other modes, perhaps due to the absence of a perfect fifth above the root, the Locrian modes cool contribution to our tonal world is to diatonically create the minor seventh flat five harmony. This distinct minor color creates the total "yearning / longing" feel within either the major or minor tonal environment, it is potentially such an essential and unique color within the system and the emerging jazz artist. Lets compare the pitches, arpeggio and create this important chord. Example 1.
|B Locrian scale||B Locrian arpeggio||B min7b5|
Also known as the half diminished chord, this Locrian chord is used many, many ways. One of the most common uses for the half diminished chord is as a part of a common Two / Five / One chord progression in the minor tonality. We can use the Locrian color to create ideas over a ii minor 7b5 chord and resolve to One via V 7b9. Example 7, using B Locrian over a half diminished / b9 cadence in A minor. Example 1a.
|ii min 7b5||V 7b9||i min 7||i min 7|
The cool standards "My Funny Valentine" and "Sugar" use the above motion quite a bit.
Another common idea using the half diminished / Locrian color similar to the above progression is to "double up" the Two / Five component of the above harmonic grouping into the Three / Six / Two / Five chord cycle. Here we simply cycle roots diatonically by perfect fourth as we approach the tonal center using the minor 7b5 on Three. Example 2.
|E - 7b5 A 7b9||D - 7 G 9||C maj 9||C maj 9|
Part of the coolness of the above idea is perhaps the rapid emerging of the minor color into the major hues.
The Three / Six / Two / Five sequence is a very common occurring chord progression in jazz standards. Besides being part of lots of tunes, it works well as an intro when getting into a tune, "outro", when getting out of a tune, vamp, to segue between sections of arrangements, the "works." Look to the harmonic resources section for more ideas for the Three / Six / Two / Five sequence. Check out the following titles that use the above changes from example 2 for further study of this important component.
"A Foggy Day", "Misty" (bridge), "Stella By Starlight", "There Will Never Be Another You", there's lots.
Here is another fairly common use, among many, for the minor 7 b5 color. This idea simply keeps a common tone in the lead while chromatically moving from the tritone downward towards the tonic. Try this progression as a cool tag on one of your arrangements where the last pitch is the tonic. Simply hold the tonic pitch while the harmony moves underneath towards One. The surprise at the end is a common artistic technique for extending the phrase just a wee bit more. Example 2a in F major.
|F# -7b5 F - 7||E - 6 Eb 13||D -7 G 9||Db maj7 C 6|
The above lick is often part of the "standard arrangement" for What a Wonderful World. Explore the tonal convergence section for more ideas with the half diminished color.
A cool and perhaps more modern cadential motion approach is to use the Locrian half diminished chord in a resolving motion towards tonic stability in the major tonality. This following motion is part of more reflective music, ballads etc. Example 3.
|A min 7 b5||Ab maj 9|
So soft and subtle a change, a longing tension to a gentle resolution. Again, a bit more modern than traditional. Cool sound huh? Here is a chart spelling out the pitches of the Aeolian mode from each of the 12 pitches of the chromatic scale. Example 4.
Here is the sound of each of the groups from the above chart. Example 5.
Got these Locrian groups under your fingers? Same pitches as Dorian, Phrygian, all of the 7 modes eh? O.k. with the modal theory?
|Where to next?|
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