Hi Walt,

Brief?! Well, here's at least a link to a 'brief' description of the rootless chord voicings played by jazz keyboard players.
http://www.jazzoasis.com/Lessons/Piano/Basic%20Chord%20Voicings.htm

Now for the not so brief part:

These keyboard chord voicings include the 3rd and 7th of a chord, but leave out the root. The reason jazz players prefer leaving out the root when comping, is because the bass player is 'already' laying down the foundataion (root) of the chord in his bass line patterns. If the keyboard player includes the root in his comping chords as well, it creates a less jazzy sound, as both the bass & piano player would essentially be 'doubling the root', over emphasizing the root tonality, which is not typically desirable in straight ahead jazz styles played by jazz keyboardists from Bill Evans to Diana Krall.

Because of certain limitations of arrangers in general, the 'rootless' chord voicings recognized by the Technics KN keyboards are actually a 'slight variation' from the actual rootless voicings I learned from my experience in jazz education , but they are still quite appropriate when you want to sound like an authentic live jazz keyboard player comping in a jazz combo setting, with the auto accompaniment playing the bass player & drum parts.Playing 'rootless' chords gives the music a more 'open' sound which is the trademark of straight ahead jazz. Most jazz tunes are based on the II-V7-I chord progression, so here are some of the rootless voicings which the KN keyboards recognizes. I encourage everyone (especially people who like to play jazz styles) to try them out and memorize these II-V-I chord progressions as it involves very little finger movement (smooth voice leading) between the chords. Hope some of you will write back and let me know what you think, and if you find these chords useful in your playing. I'm confident it will expand your arranger keyboard playing possibilities and provide a more authentic jazzier sound as well. - Scott

Bill Evans: A Type IIm9-V13-I69 Chord Voicings
(both split & full keyboard modes):

Cm7(9): (Eb-Bb-D)
Dbm7(9): (E-B-Eb)
Dm7(9): (F-C-E)
Ebm7(9): (Gb-Db-F)
Em7(9): (G-D-F#)
Fm7(9): (Ab-Eb-G)
F#m7(9): (A-E-G#)
Gm7(9): (Bb-F-A)
Abm7(9): B-Gb-Bb)
Am7(9): (C-G-B)
Bbm7(9): (Db-Ab-C)
Bm7(9): (D-A-C#)

C13: (Bb-E-A)
C#13: (B-F-A#)
D13: (C-F#-B)
Eb13: (Db-G-C)
E13: (D-G#-C#)
F13: (Eb-A-D)
F#13: (E-A#-D#)
G13: (F-B-E)
Ab13: (Gb-C-F)
A13: (G-C#-F#)
Bb13: (Ab-D-G)
B13: (A-D#-G#)

C69: (E-A-D)
Db69: (F-Bb-Eb)
D69: (F#-B-E)
Eb69: (G-C-F)
E69: (G#-C#-F#)
F69: (A-D-G)
F#69: (A#-D#-G#)
G69: (B-E-A)
Ab69: (C-F-Bb)
A69: (C#-F#-B)
Bb69: (D-G-C)
B69: (D#-G#-C#)


B Type IIm7-V13-Imaj7 Chord Voicings
(both split & full keyboard modes):

Cm7: (Bb-C-Eb-G)
Dbm7: (B-Db-E-Ab)
Dm7: (C-D-F-A)
Ebm7: (Db-Eb-Gb-Bb)
Em7: (D-E-G-B)
Fm7: (Eb-F-Ab-C)
F#m7: (E-F#-A-C#)
Gm7: (F-G-Bb-D)
Abm7: (Gb-Ab-B-Eb)
Am7: (G-A-C-E)
Bbm7: (Ab-Bb-Db-F)
Bm7: (A-B-D-F#)

C13: (E-A-Bb-D)
C#13: (F-A#-B-D#)
D13: (F#-B-C-E)
Eb13: (G-C-Db-F)
E13: (G#-C#-D-F#)
F13: (A-D-Eb-G)
F#13: (A#-D#-E-G#)
G13: (B-E-F-A)
Ab13: (C-F-Gb-Bb)
A13: (C#-F#-G-B)
Bb13: (D-G-Ab-C)
B13: (D#-G#-A-C#)

Cmaj7: (B-C-E-G)
Dbmaj7: (C-Db-F-Ab)
Dmaj7: (C#-D-F#-A)
Ebmaj7: (D-Eb-G-Bb)
Emaj7: (D#-E-G#-B)
Fmaj7: (E-F-A-C)
F#maj7: (F-F#-A#-C#)
Gmaj7: (F#-G-B-D)
Abmaj7: (G-Ab-C-Eb)
Amaj7: (G#-A-C#-E)
Bbmaj7: (A-Bb-D-F)
Bmaj7: (A#-B-D#-F#)


3 note Dominant Rootless Chords
(both split & full keboard modes):

C7(9): (E-Bb-D)
C#7(9): (F-B-D#)
D7(9): (F#-C-E)
Eb7(9): (G-Db-F)
E7(9): (G#-D-F#)
F7(9): (A-Eb-G)
F#7(9): (Bb-E-G#)
G7(9): (B-F-A)
Ab7(9): (C-Gb-Bb)
A7(9): (C#-G-B)
Bb7(9): (D-Ab-C)
B7(9): (D#-A-C#)

C13: (Bb-D-E-A)
C#13: (B-D#-F-A#)
D13: (C-E-F#-B)
Eb13: (Db-F-G-C)
E13: (D-F#-G#-C#)
F13: (Eb-G-A-D)
F#13: (E-G#-A#-D#)
G13: (F-A-B-E)
Ab13: (Gb-Bb-C-F)
A13: (G-B-C#-F#)
Bb13: (Ab-C-D-G)
B13: (A-C#-D#-G#)

C7: (Bb-E-G)
C#7: (B-F-G#)
D7: (C-F#-A)
Eb7: (Db-G-Bb)
E7: (D-G#-B)
F7: (Eb-A-C)
F#7: (E-A#-C#)
G7: (F-B-D)
Ab7: (Gb-C-Eb)
A7: (G-C#-E)
Bb7: (Ab-D-F)
B7: (A-D#-F#)


Two Handed Open Voicing Chords (great for coming jazz blues)
(full keyboard mode ONLY):

Chord Name (lt hand) (rt hand)
C13: (Bb-E-A) (D-G-C)
C#13: (B-F-A#) (D#-G#-C#)
D13: (C-F#-B) (E-A-D)
Eb13: (Db-G-C) (F-Bb-Eb)
E13: (D-G#-C#) (F#-B-E)
F13: (Eb-A-D) (G-C-F)
F#13: (E-A#-D#) (G#-C#-F#)
G13: (F-B-E) (A-D-G)
Ab13: (Gb-C-F) (Bb-Eb-Ab)
A13: (G-C#-F#) (B-E-A)
Bb13: (Ab-D-G) (C-F-Bb)
B13: (A-D#-G#) (C#-F#-B)

C7(9): (E-Bb-D) (G-C)
C#7(9): (F-B-D#) (G#-C#)
D7(9): (F#-C-E) (A-D)
Eb7(9): (G-Db-F) (Bb-Eb)
E7(9): (G#-D-F#) (B-E)
F7(9): (A-Eb-G) (C-F)
F#7(9): (Bb-E-G#) (C#-F#)
G7(9): (B-F-A) (D-G)
Ab7(9): (C-Gb-Bb) (Eb-Ab)
A7(9): (C#-G-B) (E-A)
Bb7(9): (D-Ab-C) (F-Bb)
B7(9): (D#-A-C#) (F#-B)



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